If you haven't used the 2 rear-most mounts on the diff (M12 blind tappings?) how about a torque reaction bar ( or tube) towards the rear of your car; & sleeve-down the elongated holes at the front (if access is possible) by bolting on a plate with a flange welded on to match the oversize in the ally. But going back to an old post of mine --there is no where on your drive train for shock load to be absorbed--it's all metal to metal--gears,prop,bearings,casing, chassis;but then that's my particular bee & lots on here don't agree,regards Bob.