Thanks for the reply. That looks like the boot. Firebird Central sells a repop that is said to be for 68-69 cars. https://www.firebirdcentral.com/ProductDetails.asp?ProductCode=TRA%2D2030&CartID=2

That is the shape of the hole as well. I’m guessing this would be the same hole a manual car would have, but that’s what I’m trying to figure out. From my research, only 1969 Camaro manual cars have this oval, rough cut hole. Couldn’t find much info on the subject relating to Firebirds.

And I thought my car was a th-350 originally, but maybe it was a powerglide? It’s got a 200-4R in it now.