Here's the most recent acquisition for the project: an NOS rear tail panel. These things were made out of one giant piece of injection-molded plastic, about five feet wide. They were extrememly fragile and always broke at the outer section where it narrows down to the thin outer extensions. This was because people tried to remove them without unbolting the two outer studs and eventually found out the hard way after they broke it into three pieces.
The original one from my car had been repaired (badly). It looked fine from the outside but from the inside you could see that it had a hacksaw blade fiberglassed onto the back to support the broken outer extension on one side. (Nice professional repair).
I found this one on ebay. Cost about $280 (actually a bargain since the only other one I've ever seen up for sale, the guy is trying to sell for $750!)
This one was stored up in the seller's attic for about 20 years. He had primed the outside but from the back you can see it was never installed: the mounting studs have never had a nut turned on them.