I recently bought my 97 F150 4x4 supercab and cannot find the problem with the cruise. I have checked all of the fuses, checked the wiring on the master cylinder. I even checked to make sure there was no voltage on the master cylinder switch when the pedal was not depressed. I can't think of anything else to check.
Hey man some 97's had a recall on the cruise control because it had a malfunction and would start fires, so the geniuses at Ford decided to fix the problem just by disconnecting the cruise control and not actually fixing it... They may have the part you need now though
As I understand it the "fix" was was to put a fuse inline at the master cylinder. This does not have that recall done but the switch does not have current when the pedal is not depressed. It would if it were faulty.