There should be a plug you need to disconnect which feed the power and speaker wiring and then the antenna wire pulls out and then the bracket that grounds and holds it in place.Then the knobs and dials.You probably need to remove the ashtray and ashtray mount to get it out.
David
http://FirstGenFirebird.org/show/closeup.mv?CarID=571 If i don't get this car back on the road soon i'm gonna go postal! On a quest for FGF knowledge 1968 Pontiac Firebird Convertible 1969 Oldsmobile Cutlass "S" Convertible *Sold*
Make your appointment with your chiropractor before you start because this won't be a comfortable job. I dropped the ashtray and the wood decorated bezel first. The bezel fastens at the bottom with screws and hooks over hidden plastic a retainer strip at the top. There is a fiber optic light pipe to light the ashtray, so be careful not to hurt that part. There is an escutchen plate that comes loose when you remove the knobs and 7/16 "pot nuts". Use a deep socket or deep nut driver for them. There are two more screws through the "sub-dash" into the front of the radio and you won't see them until you drop the wood grain dash escutcheon. One more bracket supports the right rear corner of the radio. There is also the antenna and power/speaker jacks. The power/speaker might latch in, I forget now. Don't force if there is a catch.
Yup, its a pain. Not like just slapping a new one in or out. Those designers back in '68 really wanted that AM radio to be mounted like a TANK! It weighs as much as a new home stereo, so be careful.
I recall having to pull the bezel, the ashtray, and several support pieces. The connectors are idiot-proof, but hard to get out if they are 38 years old. Take your time, save ALL nuts and bolts for future projects. If you are pulling or replacing the dash center speaker, then the AC/Heat assembly needs to be loose. Thats a pain too, one that will make you punch a few concrete walls in anger!!!
BUT....take it easy. Relax. Enjoy!
'68 428 HO M3 Monster, 4-on-the-floor! Need I say more?