Everything Bill said and like him I also like to run my solenoid wire through the govenor so one doesn't forget and leave the switch on and start off with the OD engaged. The govenor atomatically disengages the OD at a little under 30mph. I have a starter button on a home made bracket that the gas linkage activates when the foot feed is pressed ALL the way to the floor--this is my (cheap) kick down button. One wire is to ground and the other to the (Dist) side of the coil. This is not as good as a regular kick down switch but unless you stomp the gas pedal to the floor and hold it there, which would kill the engine, it works fine. Anything that momentarily kills the power will kick it into under drive and you can prove this by quickly turning the switch off and back on which will put it into under drive. This does not apply to a system that has something like a toggle switch that feeds current directly to the solenoid.

Evan