Thanks Gary, I shoud have thought of that. Towing was my life for 4 years and that is a basic concept. I was stressed out this weekend trying to wire up the tow lights.

It was easy once I thought it through. Couldn't figure out why there wasn't any power to the coach end of the diodes, couple hours later told myself that you need to hook up the coach to have coach power to the wires. Doh :-[