Im currently using these wheels
They are 15x8 and my tire size is 32. They are Bfg A/t and needless to say Im very impressed with them. They drive like a road tire and in mud they hold their own. When you are on sand or snow they really stand above any other tire Ive used.
Im running around 1.75 to 2 inch wheel spacers. Im not sure of the exact width and the guy I got them from said he thought 2 inches but wasnt sure. They really helped in bringing the tires out good and I think its one of my favorite things about the truck other than the wheels and tires.
I do still have the wheels were mounted on the truck. I also have the first factory set of wheels and tires that I will be selling soon. I may keep the m/t wheels as spares Im not sure at this point.