You've already got as big as you can go up front by you having a 4x4. And the rear, if you even have one or want to upgrade, you can put in a BroncoII rear sway bar that's 1" diameter. Bigger = better for handing. Stock rear on a ranger is like a puny 1/2"(or something rediculous like that).
'01 XLT disguised as a '03 Fx4 Level II.