I tried doing that around 1976...drilled and tapped a hole, installed a grease nipple but it didn't work as I had hoped. To get the nipple where it was accessible to my grease gun it stuck out too far and interfered with the hinge pocket in the door. Could have been the way I did it and maybe somebody else figured out how to do it differently. All I managed to do was make the oil hole much larger.

~ Jon
1952 1/2 ton with 1959 235 | T5 with 3.07 rear end