I HAVE A 65 MUSTANG WITH A 1987 5.0 MOTOR, O2 SENSORS STAY HEATED WITH KEY OFF. I KNOW WIRING IS CROSSED BUT NOT SURE WHERE TO START, CAN SOMEBODY HELP.

 

I would get a wiring schematic and trace your wiring first, if you cant get a diagram, try:
SBFtech.com (forums). If you cant find it with a search there, look up "Joel", he should be able to direct you to a schematic...