I used some sturdy 16 gauge metal to frame the inside of the headlight buckets, which butt up against the bottom of the A pillar. It also goes a long way to keeping each side somewhat symmetrical. The belly pan - out behind my house is about two dozen old cars and trucks, leftovers from a long-dead auto wreckers yard, circa 1962. I liberated the roof off of a very rusty '48 Mercury truck cab with my sawszall. Its a wonderful blend of compound curves, much needed to take the side contours of the body and transition to the front bottom shape. This is a part I'd have a heck of a time fashioning from scratch. Best part: it was free! I sectioned the roof for it's good bits, and inserted a chunk of the original van's roof skin to bridge the two sides.