Is there a difference besides and SS tag on the glove box door and the way the lock is installed?
X2 On that. Or it may not be the lock but the tab that over the lock the little lever hits when you close it they are a pain to adjust if they have been taken off. I like to have never got mine right.SS and non SS have the same glove box door. Just one will say SS and one will say Nova. 66 has a plastic piece that's about a 1/2" thick that screws on to the actual door.
66 100 models did'nt have the plastic, just a flat steel door. 67's has a thin plastic piece over the door.
If you're having issues with the lock, I would say you have the wrong door or wrong lock.