Just curious... what is the rear spoiler on my '83 Z28 made of? It feels like fibreglass, but im not sure. BTW, its the factory spoiler.

Yep its fiberglass. Pita to replace the studs on the center spoiler when they get stipped out.

So... if this thing is fibreglass, is it possible to add more to it to make it a little taller?

Yep, if you do it correctly where it doenst seperate from the spoiler from slaming the hatch down and normal driving wear then everything should be fine.

Interesting...

took me a while to fabricate, but i bolted and glassed a 2nd gen camaro spoiler onto the trunk of my 91 stang, i used the side peices and glassed them into 1 peice and cut the ends off where the quarter ends, it look like a new monte calro ss wing