4.10s at least. :thumbsup: but regearing is an expensive proposition (300-500 per axle). Usually a better option is finding junkyard axles with the gears you want. 4.10s are usually found in 2.5L/5speed XJ/MJ fronts. and 4.10s are fairly common in Explorer 8.8 rear axles.
also, 33x10.5" tires are much easier to fit than 33x12.5". :thumbsup:
WJ arms work for lifts up to 2", maybe 3" if your truck has enough adjustment in the control arm mounts. They are the same length as MJ LCAs, but have a bend in them for tire clearance.