W124, Diesel Engine Repair

I have narrowed the cause of my non-functioning cruise control to the actuator.
I've read that they can be repairable. But I can't find the specifics about it.
It seems the potentiometer part of it isn't working, so to my mind it sounds like posibly a good cleaning maybe will do the trick. I don't know.
I haven't taken it off the car yet.
Thanks in advance.
mike

My 87 300D has a cruise control with a mind of it's own. Sometimes it works, most of the time just intermittently. I am wondering if anyone knows of a kit to fix, and including instructions for swapping out?

Thanks so much,
Roger