Wanted to replace the busted crap aftermarket pos tapedeck someone installed years ago. Got ahold of an old oem radio because, hey, I wanna listen to the radio.

Went to swap only to discover the car's radio connector plug is long since hacked away. I could make it work (most of the speaker wires are labeled) but I don't know which wires do what on the back of the 2120 (they're mounted together into a plug for what used to be easy install.)

Wondering if anybody can identify the seven wires running out the back of this radio. Red, White, Blue, Thick Black, Blue w/white stripe, White w/blue stripe, Blue w/ fuse housing.

Adding a picture below. It's from another forum, but the model is the same.

Thanks!