I'm getting a lot of play in my steering in my 1991 pontiac firebird 3.1L ever since I bent the knuckle. I'm looking at replacing the power steering gearbox since that is why I'm getting the play.

Thing is firebirds in my area are rare. From what I've been reading 82-92 camaros and firebirds have a lot of parts in common. That's how I replaced my knuckle... from a camaro at a junkyard in my area.

Would the power steering gearbox off a 89 or 92 Camaro fit on my 91' firebird?

 

Yes, they are the same basically, some Camaros and Trans Ams had close ratio steering boxes(considered an upgrade), but all of them from 82-92 should bolt directly to your Firebird.