I have a 1998 12V that I converted from a 47RE to a NV4500. I would like it it I could get my cruise control to work. The cruise control light comes on but doesn't set speed.
I was told that the speed sensor is in the rear end, but the 47re had a output sensor on the back of it. The NV4500 only has backup light wires on it.

 

'98s are so much different electrically than the other 12 valves.
If I'm not mistaken the ground speed signal that the computer uses comes from the rear differential sensor under 30 mph and from the tranny or t-case when faster.
Sounds like you somehow need a sensor on the tranny.
Wonder if your ABS works too.

 

I guess I need to find a 98 12v with a stock manual to figure it out.