I have an electric motor on the driver's door that has stripped adjustment screws that I'm trying to replace. From my understanding early 84's have different sideview mirrors that the rest of C4's.  I'm not sure whether the inside motor is a different part number though from early to late.

Wow...that's a good question! It's something that ya just never really think about...lectric mirror motors.
I'd be interested in this too, just for the information. I don't know why the '84 would be different from the other years, but I guess it's possible. Hopefully someone here might have some insight.

dont even see just the motor listed. may want to see if you can get a used one.

I have every '84 GM Parts and Service Manual at home (including all of the updates). I will take a look this weekend and see what I can dig up.

I pulled out the illustrated parts manual, and found the GM part numbers. Unfortunately it lists the entire mirror as one unit, and does not separate the mirror glass, motor, etc.... out. If you want a copy of the page from the illustrated parts manual, just let me know.