If you watch the middle of the video you will see how I connect everything. I have another video out there and search GM 2 speed wiper motor of other people testing the same thing
How is the motor returning to park position if you have removed the power? The second motor looks a lot like the one on a 1964 Cadillac. I'm currently trying to debug operation on a 1964 Cadillac.
Hope the second part of the video helped. Yes positive to the central terminal only. The first terminal is your ground and you need a jumper from the first terminal to use for the 3rd terminal.
How did you remove from the car? I tried to remove mine, but when I pulled it, it didn’t move. I was trying to figure out how to disconnect from the wiper arm.