Dennis,
A permanent magnet motor will reverse when you swap leads. These would be like the Grainger replacement motors some folks use in the heater.
The original motors were series wound motors...they won't reverse without reconnecting them internally. The starter is series wound. It won't start the truck backwards if you reverse your battery cables!!
I need to apologize for hijacking your original question...I really didn't intend on stirring up such a ruckus. I'm now officially a one wire guy!
Stuart
