Is this oil pressure ok?
I'm shocked the manuals list such low oil pressures? My 01 5.9L Ram runs 30-35lbs at idle and that's with 200K.
When my 72 Charger had low oil pressure at idle (it was about 8lbs) I had spun a crank bearing on a very worn out engine.
If you say this engine is rebuilt, I would think you'd have much higher idle pressure. I'm assuming you installed new bearings all the way through that is.