Installing radio in a 1100

I'm installing a radio in my 1100 and I'm a bit spun out on the wiring. I found a nine pin block with 7 wires. 4 pink-1 black-1 white/green tracer-1 red/white tracer. I assume the black is ground, the red/white tracer is switched power. The white/green tracer could be constant power. The pink wires must be speakers. They have colored coded dots on them, but I have no idea which is ground nor which is left or right. I can pull the headliner and figure it out, but I'm hoping someone knows what's what before I do that.

Thanks, John

Installing radio in a 1100