Do you hate your perky butt?  Well, here's your chance to drop your bum and give it that old school look.

There are several items that need to be considered before attempting this modification.

1 .It will open the door jam slightly. On a new kit, the doors are slightly oversized, on my car the driver’s side was about perfect, but the passenger side had been trimmed more, and will need about 1/8 built up on the door or jam.
2. The roll-bar holes will shift rearward a small amount, on mine I had to open the front two about an 1/8" but the rear lined up perfectly (they may have been off to begin with , I didn’t fit it up till I was done) The trim plates will cover the gap.
3. The aluminum trunk side panels must be trimmed along with the rear edge of the lower trunk floor. A small 1.5"x 3" hole is notched in the rear edge as well, to allow the trunk latch to pass through the floor and engage the latch pin, which will now fall just below the floor.
4. A small bracket will be fabricated to receive the lowered latch-pin. It will attach the bottom of the lower 3/4 tube, flush with the rear of the tube and tapped for the 10/24 latch pin screw.
5. A small enclosure will be needed to create a pocket under the latch-pin. A molded fiberglass piece (similar to the str shaft cover) or bent out of aluminum with a flange to rivet to the trunk floor.
6. The trunk hoop will need to be dropped about 1/2".
7. Gas fill hose will need to be trimmed to fit.

If you feel confident with making these small changes, then read on.

1. With the rear cockpit wall in place, the trunk hoop removed and the trunk side panels off (but drilled for rivets (frame as well) and with the tube outlines still present), mount the body at the sides and nose, check the front to be sure its centered on frame.

2. At the rear q.j. mounts I used four 1/2'' union nuts (check hardware store servalite brand look like 1.25" long nuts) I used a short bolt to attach them to the frame and used a bolt from the outside going in and that gave me a repeatable setup, which isn’t possible with the loose 7/16 bolts and spacers (you want things to go in the same position every time you are fitting and the stock setup allows too much moving around each time you mount it. the holes are 1/2 in the body and frame, so things are nice and solid . It also avoids the hassle of dropping the gas tank to tighten the q jacks when everything is done.

3. Center the rear of the body over the frame, and disregard the original holes (I made the mistake of using them as a reference, only to find them to be off by .25 inch) You can check this by measuring wheel well opening to upper shock bracket on each side, nudge around until its as close as you can get it (I couldn’t get mine perfect, but its close. I wanted as much drop as I could get, so I let the body come down as far as possible, which is limited by the 3/4 tubes in the trunk at the back corners where the three tubes converge. With a thin shim on the top of the tube for a little clearance when finished you’re ready to drill the new q jack holes in the body now. Use a short 1/2 bolt screwed into the union nut to project the position of the hole onto the inside of the body. Drill a somewhat smaller hole and use a 5/16 or 3/8 bolt to test your alignment, using a rd file to change it if it’s off. Forget about the spacers for now, (which will need to be shortened and will still fit the 1/2 bolts). Once the four q jack bolts are in, take a look, its now officially a "fordfun drop butt special" tm. Try the doors on, and see how the gap along the back edge looks, on mine they weren’t trimmed the same amount, (your hoping they oversized them generously because this opens the doorway slightly) the drivers side is a perfect fit, but the passenger was trimmed more and has a little too much gap at the back edge. I'll have to build the door edge, or jam about 1/8.

4. Now we can cut the trunk sidewall to fit. Assuming you’ve traced the aluminum and drilled it, now you need to make 2 patterns, one for each side (in theory one would do it, but i tried that and almost cut off too much on one side so I recommend doing each one separately. Take a piece of stiff cardboard and trace the aluminum side panel onto it. Cut it out and with the help of an assistant , hold it tight against the tubing framework, and up against the inside of the body. With it fitting as snugly as possible have your helper trace the outline of the tubes from the inside of the trunk, just as you did with the original aluminum panel. Now cut out a few key intersection points on the pattern, leaving the tube areas intact .

Now overlap the pattern onto the panel of that side and line up the tubing outline at the points that you cut away the pattern with the tubing outline that you made for drilling the aluminum panel. When you feel good about it, mark the body edge of the pattern onto the aluminum. Once you cut it down, place the alum panel into position and cleco or temp rivet into place in a few spots. Now it will need to be trimmed again for rubber bulb seal (I know, kind of a pain, but you don’t want to cut too much off and ruin it) Take a compass and set it at 3/8" (you want a 3/8 gap between the body and edge for seal clearance) use the compass to scribe a line on the panel for trimming. (This will taper out along the top near the front and at the back over the corner, so don’t just assume you can trim 3/8 off the whole panel). When you’ve scribed them you can cut them and test fit again before final riveting, one thing that I found handy is that you can leave the body attached at the front LOWER mounting hole and raise the back end up without having to take the body clear off when you need room to work back there, just prop it up at the area ahead of the trunk opening and make sure the 36" brace is in the cockpit.

5. The bulb seal will have to be cut and a short section left out (I'm filling the gap with the kit provided weather-strip) where the top 3/4 tube comes so close to the aluminum edge that the bulb seal cant fit down over it (see pics on my thread ).

6. Raise body, insert the lower floor temporarily and replace the body, you may encounter some rubbing between the rear edge of the floor and the trunk lower lip which wont allow the aluminum to lay flat, climb underneath and mark areas of interference, trim until the lower aluminum fits nice and flush with the trunk lip, Silicone will be used here on final install, and a short piece of bulb seal on each end just past the trunk lip. You’ll need a hole for the trunk latch, it will be off centered to accommodate the latch coming from one side. By laying the trunk lid on, with the latch assembled to it, you can see where the hole needs to be. (I'll try to get some pics of the hole for posting) There is one on my thread.

7. The trunk hoop can go in now , you can either weld it in place, or weld tabs to each end and rivet it into place. I attached the hinges so that they could guide me in the fore, aft positioning of the hoop ,using the brackets that clamp onto the hoop for guidance , make sure to leave a little gap to accommodate the weather-strip that goes between it and the body.

8. Measure the gap between the union nut and the body and cut the q j spacers to fit (allow room for a washer between the body and spacer) and then buy 1/2 bolts that are long enough to fit the qj and spacers and thread into the union nut as deeply as possible.

9. Now we can fabricate a small bracket to screw the 10/24 latch-pin bolt into. A short piece of 3/4" by 1/8" thick angle about 1.5 long will work. Insert the bolt through the hole in the body, across the opening you cut in the floor and under the aluminum lip. It will come under the lower 3/4 tube. Hold it level and note the point that it will need to screw into your bracket. Drill two holes on one edge of the angle to attach it to the 3/4 tube, and one in the middle of the other side that will be tapped for the 10/24 bolt. (now use that mental note you made).
Under the car, thread the bracket onto the bolt, square things up and mark the screw holes on the bottom of the 3/4 for attaching the bracket.

A Small cover will be needed to go under the latch-pin and riveted to the opening to create a weather tight pocket. It'll need to be deep enough to allow the latch on the trunk to come around the latch-pin. I haven’t decided what I will use here. Molding one out of glass would be easiest, but an aluminum pocket would look nicer.

 

That’s about it, take your time and make sure you want to make the mods before you start cutting things up. You WILL LOSE some trunk height, something to consider, and the doors may have a larger gap than mine do (depends on how close they cut them at the factory). To me, I wanted the car to look right at whatever cost. (which by the way, didn’t cost much at all!) If you have any questions, don’t hesitate to write. I have put alot of time into thinking this modification out, and I'm glad to share it with the FFR community, all I ask of you is the credit for coming up with it, so if anyone asks tell them you did the FORDFUN DROP BUTT MOD!

* * * * * * * *  BELOW: UPDATED 4-2007 * * * * * * * * *

ANSWERS:

(M.D.) I have seen some people make a small box so that there is room for the latch pin, but I ended up just cutting a slot in the aluminum for the catch to drop down into. Holds just fine.

QUESTION: Snkbte, Thanks for the pic. That is what I was thinking. On mine if I lower the rear 1.5" or so the lower lip would be equal with the trunk opening. Make sense? That notched pocket for the latch wouldn't have been enough.

ANSWER: If you drop the body 1 1/2", just make the extended panel 1 1/2" longer. That way everything moves the same amount, and everything fits( and seals) like it was designed. I have a number of pictures I took of the frame work etc when I did mine.

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