How do you do the wiring in an 2002 Avalon stereo?

I bought a kit from all places, Wal-Mart. Turns out I bought the plastic parts thinking it had the wiring along with it but it didn't. But what it did have was the wiring diagram and I was able to match our 1999 Avalon with the wiring with the new stereo. With lots of thread baring and joining together, it works perfectly. Later at Wal-Mart, they do have the wiring kit that would have made it a whole lot easier.