On every B44 diff I've built the kit spacings haven't been right! I always add enough shims on to the diff to make sure there is practically no sideways movement at all, and always by putting the shims onto the side that pushes the bevel gears together. Close fitting, but it must still be free spinning!
Can be quite a few shims as the gears wear down too.
Doing that I've never stripped one ever...and replace the bevel gears occasionally as they do slowly wear down.
