Diesel availability is no problem here. I've had a diesel before (07 Classic Silverado 2500HD) and loved it, only regrets were that it was an extended cab instead of a crew cab and that it had IFS.
To be quite honest, diesel is by far my motor preference, I freakin love diesels. BUT: I can't afford to outfit a diesel to Power Wagon specs, also I am concerned about the trail capability of the Cummins due to the 1000lbs more weight in the nose! (OH, nother note: if I buy diesel, it's 2012 all the way, I do NOT wanna hafta mess with cat piss, LOL! (Don't want 2013 Urea system))
Plans for the truck (either one):
3" lift (likely Carli starter kit but, upgraded with control arms, trackbar, and maybe flexy springs. I am open to other suggestions though!)
37" tires (looking at Toyo Open Country mud terrains) on stock wheels (once again, open to suggestions)
Rocksliders (likely Aluminess, but if anybody knows of other options to check out, lemme know!)
Some kind of speedo correction, anybody know of a cheap recalibrator for tire size? (kinda like the AEV ProCal for JKs?)
The Power Wagon's 4.56 gears are nice for 37s as it's just like putting 265/75R16 tires on a 3.73 geared Hemi Ram. (in terms of tire size vs gear ratio) If I were to go with the diesel, I'd have to swap ARB lockers in front and rear and regear.
Towing- I don't see myself needing more than the 10,800lb rating of the Power Wagon BUT, I do know the diesel would pull that load easier. I wish the Power Wagon had a higher payload rating though, it is only rated at 1,880lbs.
On the topic of a used truck, I'd rather buy new. I looked for a used truck for months with no success. The few trucks I found that I liked either got sold before I got to them or the owner decided to keep in one case, LOL!
Thanks for all the opinions and advice y'all! Keep it coming!