If they are the Hughes 5321, they ARE oil through lifters. I tell you man, if that's the case, you have plenty of oil pressure. Oil is just gettin by the pushrod is all. That would be the last thing I would worry about.
There is a whole thread about guys having the same issue with low oil pressure using those bam lifters. They will give you the same problem. You want the comp cams lifters that are solid all the way down nod a high volume pump if you do not already have one.