With a posi unit in a street car I probably wouldn't install the "green" axle (ball) bearings. The Timken tapered axle bearings are a lot tougher than the "green" axle bearings are, especailly on a street car I had to use the "green" axle bearings in my 8 3/4 due to using the 35 spline axles and spool, it is in my Duster that I drive a little on the street(less than 2000 miles a yr.) and race it at the track 3 to 6 times a year. I have change gear ratio and center section about five times in the last four years, no trouble with the axle bearings yet If I could have used a Timken tapered axle bearings in that rear end I would have I'm considering installing a Dana 60 in the car now (due to breakage on the ladder bar mounts on the housing ),if I do it will have a Dana clutch type posi and a set of stock type axle bearings in it, not the "green bearings like now