My car is an early production 1991 T/A. The t-tops are GM glass, and the they have a separate lock that is different from every other lock on the car. I'm guessing my car originally came with Lexan t-tops that were replaced with glass t-tops from another car, although I do have a separate key for them.

My driver's side t-top has a large gouge in the glass that lines up with a large dent in the roof (not sure what happened there). I got a glass t-top from a late production 1992 Firebird from the pullapart yesterday, but after taking the trim panel off, the ends of the pins are totally different from the t-tops on my car. I had planned to swap the latch assembly (with the pins and lock cylinder attached) out with my gouged t-top and use the new t-top on the car with my old latch assembly, but I'm starting to wonder if this latch assembly is even compatible with my car.

The pins on my current t-tops have large plastic caps on the ends of the pins, whereas the pins on the '92 top I got are just bare metal with no caps. Also the holes that the pins go through on the t-tops themselves are totally different sizes (old ones are much larger than the '92 top to accommodate the plastic caps). Usually I'd just swap out the hardware that the latch mounts to, but It's sealed to the glass.

The pins of the new t-top go in the holes in the body okay, but I have no weatherstripping on the car right now, so not sure if the fit is going to be tight enough.

What's the deal here? I thought that other than GM vs. C&C, and early (82-83?) hook style vs. pins on later cars, that all third gen t-tops were compatible with each other. I was not at all aware that they had changed the size of the pins as well!

Should I just drill out the rivets in the lock cylinder and just switch the lock cylinders without swapping the whole latch/pin assembly over, or is that even going to work with my car? I'm hoping that I don't need to go back and get the other t-top and the bushings that go into the body, it's a lonnng drive back down there, and I really don't want to shell out another $45 and have to swap another lock cylinder over to have matching t-tops, all because of a scratch on the driver's side glass.

 

There is a hook style, small pin and large pin latch system for GM t-tops.
Im not 100% sure on the cut off days but I thought the large pined t-tops came around the time of the airbag and t-top seal update someplace in 90?
soo
Hooks from 82-84?
small pin from 85-90?
large pn from 90-91?

Large and small pins can be swapped. Push in on the big plastic part around the pin, its spring loaded. I think its more of a rattle stopper of some kind maybe??

 

Alright, so I guess I'll just take the caps off my old latch assembly and use it bare. I don't like the fact that I'm losing added vibration-helping stuff, but whatever.

Now on to my next question...I have already purchased full weatherstripping for a pre-1992 car...will this weatherstripping still work on this 1992 t-top? Only real difference I noticed was two flaps on the side weatherstripping that fit into notches on the t-top body.

 

Yeah the seals interchange. There are a few differences in the seals if you set them side by side. Like the drain channels an that bracing.. Make sure the Ttop seal is the correct one for the body seals.

 

I forgot to close the latch on the passenger t-top and flew off like a jet pilots ejector seat but I was given another. One side has the small pin metal only type, the other has side has the black plastic outer shell both work fine.
When closing the latch the black outer piece hits the car while inner metal piece continues into the latch receptacle (not sure of the correct name) but I hope you my meaning.

 

Okay cool, yeah I got a complete '91 weatherstripping set (minus the hatch and hood), so I should be good to go then. Thanks for your help guys!

 

ok so im doing the same thing to my ttops..i have a 92 firebird and have the plastic ones with a large pin...i have 2 sets of the plastic so i took apart one of them(didnt know so much to take out just to get to the pins) however there the pins go through are different on the glass tops i want to swap with..so is there anyway of changing the holes on the body of the car so that it shuts tightly with no spacing like my plastic ones do or do i have to drill a bigger hole on the glass tops to swap the latch/lock assembly

 

Using my phone so I can't link.
Search

1ADan

He has pics of before during & after taking them apart for drip edge swap.
Maybe you can see what you're looking for?

 

Just saw my name pop up. Unfortunately I don't have any photos of the car side, but you can see all the angles of the t-tops here