Alright I just got back from looking at it.
Theres no way its 475 hp. Its peppy but I'd say low to mid 300s. No surprise there. The headers are wrapped and they smoke when the car is shut off (when the engine fan stops blowing). He said this is normal for wrapped headers and that I could unwrap them to make it stop. I've never had any experience with wrapped headers so I really dont know what to believe.
He claims that the block is a 4 bolt main block. I did find reference to 4 bolt mains being available on 68s L79s here.
He claims he made his own engine mounts as well as coil over mounts. I didnt get the car on a lift but what I saw looked professional. He also claims the rear is an R200 from one of the other Z parts cars he had. There was a lot of aftermarket suspension components, especially in the rear.
The fiberglass portions of the body were done sloppily. The hood fits decently, the fenders fit pretty well, the nose is bubba'ed and the lip is loosely riveted on. The rear facia needs some work as well. There is a little rust on the metal portions of the body like around the windshield but its not bad at all. The paint is in pretty bad shape. Theres at least 4 spots where the paint has an issue like the strap mark on the hood. It appears he's touched them up with a rattle can.
He has a mechanical pop lock on the driver door and an electric one on the passenger door. Neither work very well.
Now he's got standard doors and the original hatch in his garage, all in great condition. No signs of rust on any of them.
I spent about an hour looking at the car and didnt make an offer. I figured I'd come back and see what the experts have to say. I'm thinking $6500 at most with the factory hatch and doors. I'd also need to get under the car for a much better inspection before I laid any cash out.
If this were a daily driver I'd have walked away right off the bat but this is supposed to be a weekend car and tuning up all the little issues with it could be fun as long as the purchase price is right.