It took a while, but I found the relay that I removed from a parts car that had the same type of antenna. It is a simple single coil double set of contacts style relay.Here is how it was done. In the de- energized state the power comes in on the red and out on the green, ground is blue to jumper to top terminal on left contact, yellow has no connection . In the energized state the power comes in on the red and now comes out on the blue and the jumper to the top terminal on the left contact has no connection, yellow is ground and green has no connection. I did not look at it when it was wired up, but I think if you wire your “up” on the green after the relay and use the “down” to energize the relay it should work.The blue goes to one wire on the motor and the yellow and green go to the other wire.