Originally Posted by Robert McEwen:
I'm thinking of wiring in a flat four prong plug directly to my tail lights/brake lights/ and turn signals. That way I can run my "trailer light wire" through the front trunk, into the cab, and into the engine bay and plug in directly to my car's lights. The brake lights etc work well enough for when I'm driving; does anyone see a reason why I couldn't use the same for when I'm towing?
If you do that, you MAY need to run a ground wire from the Speedster's ground to the tow vehicle's ground to get the lights to work.
Or, the tow light wiring harness may include a ground wire back to the tow vehicle ground.
But in either case, you could have issues with voltage feeding back from the Speedster's lights, through the Speedster's fuse box, and energizing some things you may not want to be running.
My gut feeling is to not use any part of the Speedster's electrical system when you're not driving it.
One beer later:
On further consideration, you probably won't have backfeeding issues if you keep the Speedster headlight and turn signal switches off and don't step on the brake pedal. You may still have to run a separate ground wire between the two cars, though.