OJ,
I wished that I would have insured that the seam on the fiberglass tank was matched better before I spent hours building the perimeter frame inside it. When it came time to put the top front section on it did not fit. I ended up cutting the body section and adding a nasty splice to make it fit. It will take more work to make this look good than it would have taken to insure that the fit was correct the first time. This was my first special construction project also. Check out all the recommendations that you get on this site, there are a lot of racers that have been there done that. Post pictures, it is amazing the things racers can spot in a photo.
I wish the best with your project.
Mike Brown