I had some sons and friends help me install the body today (Mk4) and I started to put the rear bolts in that secure the body to the frame. I can't get to the back side of the frame plates that these bolts go thru to get a nut on them due to the gas tank. The FF manual shows installing the body on a frame with no gas tank or trunk floor in, but I've got the chassis finished. Am I missing something? Does the gas tank have to be removed in order to get the nuts on these bolts? If so, it would have been nice to mention this in the manual. Thanks for any advice you can give.