I know this is an old thread and my response is probably WAY past helping you, but for anyone else interested, it's INCREDIBLY easy to add cruise-control to a 2nd generation Dakota that wasn't originally built with it. At least, it was for my 2002 SXT. All you need to do is go to a junkyard and find a Dakota (I'm assuming a Durango of the same year would work, too), and cannibalize the following parts from it:
1. The cruise-control switches
2. The wire harness in the steering wheel (behind the airbag) that connects the switches to the clockspring
3. The back cover on the steering wheel (the back cover on a Dakota/Durango without cruise isn't made for the cruise-control switches
4. The cruise-control servo from under the hood, with the vacuum line and throttle cable
The studs under the hood (passenger-side) that the servo mounts to are already there (you just need to source three nuts); as is the vacuum line running across the upper firewall (it has a rubber cap on it where the cruise vacuum line attaches to it), and there's a place on the throttle cable assembly where the cruise cable simply snaps into place. There's also three connectors on the clockspring, and only the far left had a plug in it (the airbag) - the middle plug is where you plug the cruise switches into (I think the far right plug is for steering wheel audio control buttons). After I installed everything, I started the truck up and pressed the cruise button, and the word "Cruise" showed up in the odometer! It works perfectly, and there was no flashing by the dealer of any kind required, although that might not be true for all 2nd gen years.
Google something like "Add cruise control to a Dakota", or search YouTube for it - there's a video showing exactly how to do this. That's how I found out about it.