Doyo

So I just bought a 2nd gen RX-7. Just now getting into cars. Though I have been around them all my life, anyway. I just started on a project car as you can see from the title.

The thing is, im not good with wiring.
The idiot I bought the car from stripped/cut the main harness from the factory wiring leading to the car. Which connects to the factory radio.

Now, im trying to sit here with my aftermarket radio, debating which color goes to what. But the main problem im having is that the factory wiring is based on a whole different color set than the aftermarket wiring colors. I just need help or at least a main diagram in which, which goes to what..