I have a BII sway bar on my 2000 2wd. Bolts right up. Holes are in the frame and everything. Its almost too easy. IIRC the BII was a tinie bit larger than the Ranger rear sway bar.
I don't know if you have on tho... But if you dont, you should get one. The best thing for a Ranger that's a daily is a rear sway. My truck still takes turns on rails even tho its lifted a little.