I am installing an aftermarket amp to a factory head unit into a 99 4 door blazer. Where should i tap the remote wire into? I've read to the big yellow 12+ switch wire, but i don't have one? The wires don't match the ones listed under the stereo wiring and install thread, minus hopefully the speaker wires. There is Dark green, dark blue, purple/white, orange, grey, and black that are not the speaker wires. Am I missing something?

 

This is what i think, ( all my radio knowledge is for pre 98 )

Orange constant +12v
Black Ground
Gray dimming switch...


Got a multimeter or something to test with?

 

so the orange would be a wire to tap into?