8.8s are cheaper and easier to find around here. cars at the strip are pulling SERIOUS times with a modded 8.8. weld the axle housings, run a girdle and forget about it. rangers i think are around 52 backing plate to backing plate. i have one at the shop i can measure but hopefully some one chimes in. my axle is hard to get at now. only down fall is the pinion is offset to one side by about 6-8 inches if i remember right. any f150 with a locker (not sure about open diff) with an 8.8 runs a 31 spline. as well as locker explorers. fx4 rangers in around 2003 ran a 31 spline torsen locker with 4.10s.

bob