[kwmech]

When you mate up the 465 to the rear of the OD unit you have to cut the nose of the bearing retainer off and machine it down to a certain thickness. That thickness is just enough for the factory input seal of the 465 leaving a small lip of about 50-60 thousandths. The back of the OD unit has a sealed bearing if I remember correctly (it's been awhile since I had mine apart)