Old Sanyo stereo wiring help

[Jokers69]

Alright, who remembers the old sanyo auto stop cassette decks? I have one that came in my car whe I bought it, the radio is most likely mid 80's or so. I don't want to replace it with something that would cut my dash, and I don't have the $$ for one of those custom autosound decks yet.

Theres a plug with eight wires coming out, it's hooked up for two back speakers right now, and works. There's a blue and green hooked up to one rear speaker, a white and yellow hooked to the other speaker, and a red power wire. That leaves a brown, a light blue and a black. Do the front speakers share a common? The back speakers each use two wires.

Does anyone have a clue as to what is the correct wireing?

Thanks.