Originally Posted by William Kisselstein

should be pretty obvious, it's a box maybe the size of half a carton of cigarettes on a bracket next to the power steering fluid reservoir (toward the right, or passenger side of it) with a cable which circles around and down just right (passenger side) of center to the throttle linkage.

These vans have two wiring harness variants. One has the plugs for cruise and one does not. Typically these vans came with one or two option packages; the package for cruise also included a tilt wheel. However the switch with cruise is interchangeable to either column. If you have no module, you will have to check if it has the wiring plugs, they are left dangling in the same area as the bracket would be and you will see two or three studs with nothing on them.

My 2002 2500 has power windows/locks and mirrors and it has the harness for cruise. I bought the parts to add it but have never gotten around to it. You need to pull the doghouse to reach into the throttle to snap the cable end into place.

The 3500 does not have any power options and does not have the plugs.

Best bet is a junkyard swap, you can probably buy the module new, but the bracket is going to be salvage only and you need the bolts for it too. That also lets you see how to snake the cable into the right place.

Supposedly if you add it on the computer will recognize it and it will work, it may need to learn it, if yours does not have it and you are able to install one, please come back and tell us how it works.