To get the cruise to work: there is a switch on the brake pedal that shuts off the cruise when you apply the brakes. IIRC, it is the one up higher with only two wires.
Bypass that switch. I used a snap lock connector to connect the two wires together w/o cutting or disconnecting anything. Apparently, applying the brake breaks the connection. You will be bypassing that so it is always connected.
I thought there would be a down side, like having to use the on/off button for everything, or the brakes don't turn it off, brake lights on all the time, etc. Everything functions normally! Doesn't make any sense, but it works.
This was RobertP's suggestion when our old 96 Cougar's cruise didn't work. I also did it to our '04 CVPI. Fixed both of them, and they work great.
97 T-Bird LX 4.6 - 80k miles
94 Supra TT Auto - street/strip car
04 CVPI- Brenda's car - 76k miles
95 T-Bird LX 4.6 - fully optioned, owned 15 years, 220k miles
96 Cougar XR-7 4.6- Brenda's car, owned 11 years, 187k miles
88 T-Bird 3.8 - first T-Bird, owned 5 years, 206k miles