I have recently acquired a 1979 Mercedes 300TD which was my great Aunt's car that was bought new in South Carolina. The only problem is that the cruise control does not function properly. When it is engaged it simply accelerates as if it is stuck at WOT. It will disengage with the brake or by pressing the handle to the off position. I did some reading that says this is most likely the cruise amplifier. Is this the most likely source? If so will the amplifeir from a 1978 300CD work in this car, b/c I have found one at a good price. Also where is the cruise amplifier located at in this car.

Thanks,
Kevin