I'm still on the fence about the rear of my car. I think about using a wing from some late model car to be different. I have the 3 piece spoiler, but due to quarters being changed the fitment is poor at best.
If I do decide to use I will have to mold them to the car and either have to grind down the tops or add to the other sides. Pice don't show that well the issues. There are gaps where the corner pieces meet the quarters thus throwing the alignment way off. How would others approach this?

 

If that is the best they will fit up,i would definitely mold them to the body.Use fiberglass though,if you try and do that with just body filler,i would guess that it would probably crack away eventually.

 

i would defiantly mold it to the body and ya use fiberglass bondo isnt made to fill gaps like that

 

Are you sure those are the correct spoiler for the year car? That's about as bad a fit as I've ever seen on one. You could remove material from the back side to get it closer, and you'll need to do something prior to any molding in with glass anyway, or it will crack out.
I would pull the pieces off and use Duraglass underneath, then bolt them down before it sets up. If the gap isn't filled first they'll flex and start cracking later. After that I'd glass them in with cloth and resin, then finish smoothing with more Duraglass. Duraglass will hold up to the trunk slamming, and with cloth it should keep it from cracking out.

 

I'm not sure about the year? 76 had no z cars.only rs's. I believe the hood is from a 79 or 80 as the scoop opens in the rear electricaly. The quarters are overlapped at the body line and welded on. I'm not changing them! I think if I try to cut the corners back I'll lose the sides. I may go back to looking at a wing. It will be different!

 

If the hood scoop is glass it can be molded, but if it's urethane I wouldn't even think of it.

 

Can you elongate the holes to get it to slide over farther?

Here's one from a show I went to a couple years back. Looks good but his line were a little off on the bottom. I intentionally held the camera so it wouldn't be seen in the pic.

 

Was the trunk lid ajar in that picture, or latch out of adjustment? Hope the center section wasn't that far off!

 

I'm not molding the scoop on. I hope that trunk is open. It looks as bad as mine. I'm not too sure from that pic if I like it on not.

 

What you don't see in the pic is the step across the bottom. I don't know if the trunk was open or not. I do remember the car was about 9 out of 10. The paint was awesome the bodywork was almost perfect. All the seams were filled. If my car didn't have a red interior, it would have been Muslane Blue.