1998 Mazda 626 Radio Wiring Diagram

I own a 1998 Mazda 626. My son replaced the stock radio with an after-market radio a few years ago. Last month, the radio died. He tried to re-install the stock radio, but the installer had cut the original wiring plug, and hard wired the new radio.

I purchased a the original male plugs from Metra, but I need to find a diagram of the original wiring for the plug to know which wire connects to which on the new plug.

Any ideas on where I can find a diagram of the original wiring?