Absolutely the first option is to flip the rear hubs and run singles on the rear. No or very low cost, better handling, greatly reduced tire wear and you end up with 4 extra spare tires. Next option, IMHO, is Air-O-Matic steering, great for city driving, parking lots, etc. Costs about $1200 though, see
http://www.m35products.com/Air-O-Matic.htm. May be able to retrofit with a 5 ton power steering package for less, but takes a fair amount of mechanical knowledge. The parts will fit with some tweaking but you need some mechanical knowlege and aptitude to get the pieces fit. Front locking hubs are nice too, in the $600 range, will improve handling a bit and improve fuel mileage also.
Definately go for the rear hub flip and rear singles though. You get all three tires on each side tracking in the same line, handles much better, and much improved tractability in the snow. You don't loose a lot of cargo capacity either, duals are derated in dual configuration, a single tire only gives up about 500 lbs per tire (2000 lbs total for the truck) vs a dual configuration. Not a serious consideration unless you are running near max capacity. If you upgrade to super singles you will have more load capacity than duals anyhow!