Finally found it

1993 OBS Speedometer and Cruise Control wiring
I've been running around with no cruise for the longest time so I thought I'd get around to fixing it. The answer was very simple with help from GasGuzzler. Remove the white DRAC box behind the glove box and pitch it in the corner. Cut the light blue wire with black stripe. Cut the red wire with white stripe. Take a butt connector and stick the two wires in one end and crimp. Take the speedometer signal wire from the PCM and crimp it to the other end. Job done.
BTW, the cruise control cable I used is from a 1998 C1500 with a Vortech V8.