AM/FM/Cassette 79-? Delco radio

I was going to take it to a friend of mine to have it looked at and cleaned. but hes out on the boat this week. so I hooked it up to see what and if it worked. it works fine for the most part. it could use a cleaning. I'm posting it here first before it hits ebay.
I picked it up at a swap meet on the guys word that it worked. and took a chance that it would work. so I paid some jack for it. but I've seen them sell , and I know what there worth. I think they were about 550.00 from GM back in the day.

make offer or trade for show quality or new interior parts for a 77

https://www.youtube.com/watch?v=A9s2bkCoKgk

Does anyone know what year, model this radio fits?

it started in 1979. it was in the t/a, camaro, vett, and others. as for the trans am it was mostly in the TATA.