1993 Century Wiring Problems

I have a 1993 Cenrury, and I am replacing the factory radio with a new cd player, but none of the wires from the old radio are labled, and the colors do not all match up, so there fore, I do not know how to splice all the wires together correctly. Any info would be very helpful. Thanks.

do the connectors not just slide in?

If you are installing an aftermarket unit, stereo stores offer adapter connectors, allowing a factory vehicle to accept aftermarket units.