pizzaguy, with the engine running there is continuous 13.5 volts to the left side limit switch. Upon completion of it opening, there is close to 0 volts. Closing, it immediately goes back to 13.5 volts. They're simply on/off switches. That is unless they're tied into the BCM to activate the spoiler at speed.

I've tested it twice and am sure of these figures. I used needles in each of the left side limit switch wires.

The raised plastic edges on the large gear are of course staggered from side-to-side. I'm unable to see but I assume the right side is on a raised section when down.

Now do you feel a regular old 10 or 20 amp double throw/double switch will work?

Another question: on the schematic you included, for the motor (bottom left) it refers to them as being Rear Spoiler Driver up, the other side down. What is a 'Driver' in BCM code?