This had to have been covered by now, but I couldn't find a thread that answered this. I have a 90 Firebird. My original arm rests have the plastic circular cover that goes over the top arm rest screw. (The cover is the same color as the arm rest.) All the 90-92 arm rests (GM) that I've bought to replace my original ones do not have this deep recessed top screw that can be covered with this plastic cover. Rather, the screw fits higher to the surface and shows when installed. (The cover won't even fit over it.) Were there two arm rest variations for 90-92? Or, am I missing something?

 

Ive only seen these covers on the Camaro deluxe armrests 88-92?All the firebird ones Ive seen had no covers and don't have a spot for them like you said

 

just from browsing through random interior parts, it seems like they changed the armrests in 88 (I think). When I bought my car it came with Camaro armrests but they didn't fit on my 89 because of the redesign

 

I bought my 92 RS new with deluxe interior and it doesn't have the plugs.