After reading through some of the posts, I have discovered my complaint about an upper limit to the cruise control speed set point is a common one. The issue is that the cruise control will not operate beyond about 81MPH. . . if I attempt to set it at a higher speed, it simply slows back down to 81MPH and maintains that speed.

I have investigated the control unit (PN 3517400). This does not appear to be the Dana controller discussed in other posts that has external adjustments for minimum speed and "centering". In fact, I opened the control box and there are not potentiometers in the circuit at all.

Does anyone have any idea on how to defeat the upper cruise control limit on this system? Or, if you have a schematic available, perhaps I would luck out and be able to reverse-engineer how the circuit limits the cruise speed. With that it might be possible to devise a hack for the circuit, to the benefit of all!