I used an "L" shape trim piece I found at a local glass shop. You can grab stuff at a local wreckers as well on a wonder thru. I also grabbed some " U" shaped stuff that I put around the door and hatch opening. Most cars have this trim around the inside door opening. Finishes it off nice. On the window I made sure to leave a 1/8 inch gap between the door and window frame for the trim. Hth

 

Yes, there should be. The manual (at least when I built mine) was very basic in content and instruction.

Remember, its your build to do as much or as little as you want.
I added seals all over the place to keep the noise and weather out as much as possible. I even added steps and flanges to the body to accomodate some seals.

Have fun.

 

I taped along the door and window frame (adjacent to the gap), then ran a bead of Permex black silicone sealer along the gap. I also ran tape along the gap on the underside, to keep the silicone in place until it dried. I used a fingertip to gently "mould" the bead into flat, uniform shape along the gap. Once it was all dried, I pulled all the tape off, and ended up with nice tight lines, and an excellent seal.

 

I found this which worked well.

Flocked Window Trim Drip Seal - FWT

I'm sure a US supplier has same.