[Maxthe222]

Hey again Joe,

Glad you're back ontop of this super unique T/A, and to answer all of your questions:

1. Not possible to get for a 1977. From factory, the radio hole in the dash was a completely different shape, it became shorter and fatter in 1978, and your PHS identifies the factory issued stereo was a U58 AM/FM Stereo, sometimes called the Red Dot Stereo (pictured below). The 1977 UN8 23 Channel CB was connected to this stereo, and is not compatible with the 1978+ style stereos.

cdn4.volusion.store/klmat-yytxn/v/vspfiles/photos/DAS-2522F-2.jpg?v-cache=1477632079

2. Single, dual rear speakers from factory wasn't a think until 1979. A good example is the 14-mile '77 SE that sold at auction, peep the rear parcel tray: gmauthority.com/blog/wp-content/uploads/2022/07/1977-Pontiac-Trans-Am-SE-interior-003-Mecum-Auctions-Starlight-Black-door-panel-seats-console-back-seat.jpg

3. As the CB was hooked up to the stereo and was completely buried in the dash, I wanna say through the rear speaker? I still have one UN8 23-channel CB, don't see how audio can come out of it.

4. I had a complete, original entire set up from a 1977 T/A that was scrapped, and sold everything (including that original special console bracket in your pic) and the original antenna and harness to a collector in the US. I can ask if he still has it, he didn't actually have a UN8 '77 from what I remember.