Here are the interesting parts. The board on the left is a power supply and interface board, which connects the various treadmill components together. That's not useful (to me). The board in the center is a generic MC60 DC motor controller board -- it's needed. And of course the motor.

The motor is equipped with a large cast iron flywheel/pulley combination -- it's the rusty part in the picture. The flywheel helps keep the treadmill from stopping abruptly. That's not desirable on a bandsaw, nor was the pulley for the ribbed drive belt something that I could easily reuse. The flywheel/pulley unscrewed (left hand threads!) from the motor easily -- just grabbed the shaft with vise-grips, and twisted the flywheel by hand.

Oh -- the third thing that cast iron piece does is act as a primitive centrifugal blower, to keep air moving through the motor. Given how different my use will be from an actual treadmill (lower speeds, lower running times, open air installation), I'm not the least bit worried about losing that extra air movement.