Is there a way to mount the 92 aero spoiler onto my 89 glass? I have a T/A w/that style spoiler and I have to use that glass to mount my newer one. I've heard the clips and mounting points are different. Is this a really big deal Would it look like crap?

It's cake. Cut off the stock 85-90 clips with a dremel as they will get in the way. Measure, drill and mount the wing. Call it a day.

Seriously though, the wing is held on by four bolts on the underside. If I had a pic of the side clips you would probably laugh. They are really not adding much, if anything they are good for lining the spoiler up. The 91/92 aerowing is a hard unflexable plastic piece, unlike the 85-90 rubber/metal frame part that needed the side clips to hold it's shape.

I don't remember if the older style spoiler has 2 or 4 bolts going through the bottom. Do you remember? If it's the same amount on both then I guess I could just use the bolts and it would be ok?

The 85-90 wing has 2 on it IIRC, 10mm. You should be able to use the body bolts that hold the rest of the car together if you don't have the original bolts. You might need a washer though, I have not had one apart in a little while so I am a little rusty.

So if the older one has 1 bolt on each side I'd have to drill 1 more hole on each side to mount the new one?

here's a pic of the newer one.

Sorry, but the holes are all in different spots. The old wing attaches to the rear area of the hatch, whereas the new one attaches towards the front. Hope you have some body filler handy!

anyone else has done this that can help me out?

Yeah I did it on my 87 GTA. The stock 85-90 Firebird wing mounts completely different than the 91-92 one. I was lucky enough to get the deck lid from the donor car too. The tips have to be fastened somehow or they look like ****, and the 85-90 wing tip clips are all wrong. You have to cut them off the glass frame and figure something else out. I went to Home Depot and got some 3/8" mirror clips (1/4" will work too, you just have to do a little bending of your own) and attacted it that way. I'll try to get some pisc, but I have the tranny out right now and that is where my focus is. It's not going to be much more work to drill 4 new holes in your deck lid. Just make sure you WELD the old holes shut, not just slap some bondo in there. The pic below shows how the tips will sit if you don't tie them to the window.

I'm getting the 92 mounting clips w/the wing--so no biggie there.
Think JB weld would work on holding the clips?
Thanks for the pic--it was really helpful. I'm kind of afraid to drill into the deck, I know the glass goes deep into the decklid. Is that even possible? To drill into it w/o breaking the glass?

I ran my 91-92 with no clips on the glass, I just used some weatherstripping to keep them from rattling on the glass.
I had it on the car for a year and it didn't have any problems.

What did you do about the different holes in the deck lid? Drill new ones?

Well, I had the pedastal spoiler on the decklid since the original decklid was gone when I bought the car.
All I did was drill 2 new holes, one on each side and bolted it on. I was able to use the frontmost bolt holes that the pedastal spoiler used.
I have no idea how the 85-90 wraparound bolt holes compare to the 91-92 spoiler.

The glass really doesn't tuck into the deck lid very far at all. Just take off the interior plastic panel and see for yourself. The glass is the same (other than the brake light mounting place) 82-92. As for if I think JB weld will work, I don't know. Give it a try, but my guess is no. There is a helluva lot of vibration back there, but JB has really suprised me a few times.