My '04 Dakota SXT has the 4-gauge instrument cluster which uses idiot lights for oil pressure and voltage indicator. Is a 6-gauge cluster a simple direct swap (eBay has them pretty cheap) or is it more involved than that?

 

What year is the cluster you want to get from?
The mileage is stored in the cluster, and the PCM.

 

I have a '03 parts truck which has almost the same exact number of miles as the '04 (and am aware of mileage disclosure requirements when selling a vehicle). From what I've read it seemed like the clusters from 01-04 might be compatible, but wasn't sure if the 2 additional gauges would work with the existing wiring and sending units or if there was some other difference (such as the PCM configuration) that would require the use of a cluster with the same combination of gauges/idiot lights as the truck was sold with.

 

It should work.

The gauges and even the idiot lights are controlled by the cluster - a computer in itself. The PCM sends signals over the PCI bus. The lights aren't hard wired.

Give it a shot.