I also had a belly pan problem. I started putting my together last week. My belly pan would not fit flush with fuse at ALL. I had to remove the entire back of the belly pan to get it to sit right. (removed about 1/8 from the back edge alltogether to get it to fit. I ended up making another former to support the shape. Works Great now.

I've installed a Webra 1.20 with Bisson Muffler....Can't wait. I'm putting my new 9C Radio in it.