Audio Systems: wiring code, radio cassette cd, toyota camry

Question
Hello Kelly, I hope you can help me. I bought a  Kenwood stereo for my wife's car, a 1994 Toyota Camry XLE. I knew to buy a converter plug for the aftermarket radio factory plug which i unpluged from the back of the radio/cassette/CD and then planned to hardwire the matching wire's, however when I got home with the harness it would not work with the Toyota because I have a "premium sound system" My problem is I have no idea what color wires do what(of course bl and red are ground and power) I did not want to cut the plug off until I have a wiring schematic ,Can you please help me with the color codes? Paul

Answer
Here is the best wiring diagram for Toyota I have.
http://www.installdr.com/Harnesses/Toyota-Wiring.pdf

As for the premium sound system, you might be able to unplug the Toyota amplifier (wherever it might be) and have the regular wires at that point. This article seems to be in order...
http://www.installdr.com/InstallDocs/Toyota/PDF/869013.pdf