Hope you've already got the rear axle. Very few S-10's ever had the 8.5" rear. I think you'll find that whenever you go "junkyarding"... The (31 spline) 8.8" Explorer is much stronger - actually Ford's remake of the 12 bolt. I have a (28 spline) Ranger axle in my S-10 and can rip off 12.0's @ 115 all day long.