Just curious...I know most GM motors are the same and have been for many years, but I've heard that there is a difference in tooth count on the gear that moves the regulator on 3rd and 4th gens. I got a free 4th gen motor and want to put it in my '91 if it'll fit.

Thanks...Ed

 

both thirdgens and fourthgens do use "scissor regulators" with "pancake motors", but the number of teeth on the gear is different.

 

Thanks for the verification.

Ed