First Truck Build

[tamiya fan]

About the same size as the body panels. I just measured the stuff I used (comes in sheets) and it is 1/16", but I think they measure it different? I would go thinner for clear window material. Just kind of study what's available. If your getting a new rear panel that's good, but the gap you have could be filled with styrene and the glue then bondo. I did mine the same way you did, had some larger gaps, and it worked for me. But trying to get it better with a new piece doesn't hurt either. Cut it out a little bigger so you can straight edge sand it straight after cutting. (just a little bigger, helps with gaps)

It's always a learning experience. Doing the back panel like you are works pretty well. (you have to put 2 notches in the bottom deck for panel to fit in) Hope this helps you out. Good luck!