The one you're looking for is the Grey/Black wire on the car's wiring loom side. Basically, all this wire needs is power and the aerial will go up. Cut this Grey/Black wire and run it to one terminal of the switch. Grab a B+ wire and run it to the other terminal of the switch. That's all you need to do. It should look like this:
Power (B+)--------->>switch--------->>Grey/Black wire-------->>Antenna
Here is the pin configuration as seen if you looking at the BACK of the wiring harness. The one you need to interrupt and take to the switch is \"H\".
