8&3/4 axle fitment problem

Put both OEM axles in with the center section out. Be sure they are fully pressed inward and held there.

Then measure the distance between the two axles.

Do the same for the dr. Diff axles.

Then rig up a way to measure the space on the inside of the center section where the axles would bottom.

That distance should be about the same as the axle spacing. When I say about I mean the adjustable OEM axles have 3/8" ? of an inch of adjustment. The green bearings have no adjustment.