Never found holes on the 72 4/4 I had either. And yes, I was another one who overgreased, blew the seal and lubricated my brake shoes.
I think some say "don't grease" as a result, but I think the axle needs a little. Clean the area around the nipple and when you've given it an occasional couple of strokes of the grease gun, remove the nipple and allow any pressure to escape before putting it back.
