Based on the two gauge issues it does look like stepper motor replacement, although the oil pressure could be the sender. Hopefully someone's not already been into the cluster and messed up any circuit board traces.
I redid the stepper motors and replaced the backlighting for a neighbor's Tahoe a few years back. Not difficult if you're familiar with a pencil soldering iron and simple circuit boards.
I've rebuilt quite a few 03-06 clusters, along with adding LED backlighting. I've done a few for some members on here actually. Done plenty of LED backlogs in AC controls and headlight switches and door switches, etc. But I have gotten away from it because it's SO time consuming to do. And the market is pretty much FLOODED with other people doing this same work for much cheaper. Could I do it that cheap? Perhaps, but I don't want to, that's why I stopped doing it. My time is worth more to me than a few extra bucks. If I'm going to spend my only off day working on clusters and doing LED conversions, then it DAMN well better be worth it. And for the most part, it wasn't. I'd rather spend my precious free time with my wife and kids.
