I took another look at it. The motor connection has just 2 wires. I checked the voltage on these. The current was good- positive one way, and negative the other way.
I was able to remove the motor via 3 torx bolts holding the motor to a 90 degree small gear box (a thick steel rivet holds this gear box in place). Motor spun in one direction only, and hardly any torque. The motor has a worm gear powering a single gear on a jackscrrew. As the gear turns, the jackscrew is run in or out, and that positions the brake pedal. This gear is plastic, and it was cracked. The motor may have been mis-indexed and kept driving at one limit, cracking the gear, or burned up as it kept driving against a non-meshing cracked gear.
The system also adjusts the accelerator pedal through a teleflex cable on the other end of the the motor. Both these have to be synchronized in their drive range. There may be an input to the computer to brake the system if the two pedals get out of synch as well.
So it is possible to test the motor, but one has to be careful the gear on the pedal jackscrew stays where it was, and the gas pedal drive cable will have to be disconnected when you test the motor, or it will not match the brake pedal postion after the test.
In summary, had the gear not been cracked, I could probably matched the numbers off the motor with another chrysler/jeep product donor and it would have worked.