[Randy in ca]

Your Seat Pan is too far ahead - looks like it needs to go to the rear about an inch or so. Also the front of the rear curved inner panel should mount on top of the rear edge of the seat pan.

I re-attached one of your pictures with some labeling. Also a couple of coupe/cabriolet pictures that I saved from somewhere - setup is exactly the same with them.

Quarter panel should be flush with the rear sub frame cross-member and the "T" molding protrudes it's depth. The wheelwell arc on the quarter panel and the rear sub frame cross-member should align when viewed from the side. Hope this helps some, Good Luck.