I signed up to get some custom body work advice in the exterior section. Here's a link to my major targa top conversion and re-paint on my 2001 Z06. The cars come as a fixed roof from GM so the targa is custom. It will use the OEM panel and trim, but the Z06 roof must be cut and have the front edge of the Corvette Coupe b-pillar trim grafted in to accept the proper hardware for the roof.
Restoration/Transformation of the Z06: Targa top conversion and repaint, etc.
Check out my thread in the exterior section if you know anything about working with SMC etc.