Cruise Control for an SC

[Porsche80]

I live in Kansas City Mo and I know there are several Porsche Cars in this area. I am trying to troubleshoot my Control Unit (factory unit). I sent it in years ago to Beckman who said there was nothing wrong with the unit, but I have been unable to get my cruise to work (no accel or anything). I have used the Bentley manual as well as posts on this board to try and resolve and I can find nothing wrong with the system. So what I am looking for is someone who lives in the KC area that has a car similar to mine 78-82 911SC, I think (mine is a 1980 911SC) whose cruise control is currently working (or at least gets some response I.E. system accelerates, but maybe it does not hold speed) that would not mine installing my unit in their car to see if mine works?
My unit is located just under the boot. I can drive my car over to your location for a quick test

Thanks