Your best bet would be 35 inch tires with your stock rims, that is with a basic 2 to 2.5 inch leveling kit. Anything wider than your stock rims, will rub on the control arms. If you do decide to go with an aftermarket rim make sure it's the same backspace dimension as the stock rims. There are various leveling kits on the market fom Rough Country, Hell Bent Steel, Top Gunz, and etc. If your looking for the performance aspect such as Kore, Carli, Lorenz, and Thuren, which all specialize in the Dodge heavy duty. I have the Kore VR coils with Fox shocks, and gave me just a little over 3 inches of lift, and the mini leaf packs for the rear. That is with 35 inch tires General Grabbers(red lettering) with the stock rims. I'm sure you know you will have to replace shocks and sway bar end links, with of course an alignment.