O.K., I've had an '84 T/A, '86 T/A, '87 Firebird, '95 T/A and a Fiero GT apart in my garage. Anybody recognize this? I tried to find a home for it on the '84 (most recent) but it doesn't seem to fit anywhere.

 

this is just a wild guess but it could be part of the battery tray. idk, just throwin it out there.

 

We have an 88 Bird and 85, 88 GT Fieros in the family. I have seen just about everything on a 3rd gen bird and I can honestly say that I bet it did not come off that. From the look of it it is about 12"x24" roughly. Going by the footprint next to it. If I use the average of 12"/ft. haha

It might help if you tell us the state of all the vehicles you listed. Which ones are running, and if not, what has been removed from them. Or what needs to be done on them.
My best guess is some sort of air dam for the radiator/cooling system.

 

Yes its 20-30 inches across. Most of the cars were stripped down to bare firewall. Engines, sheet metal removed. Only the 84 T/A and Fiero are back on the road.

 

haha. ok sorry, i have to laugh. this is a perfect example of why you should label all of your parts. again sorry, its just kind of funny. ummmm..... i don't know where it came from, but yea, like said before, it looks like it could be from a battery tray.

 

It must be off a 3rdgen bird, because I had one laying around for the longest time, I never could figure out what it was though.

My friend and I have parted so many 3rdgen birds though, I couldn't tell you which year it came off of.