New motor, sounds awful?

Which RHS heads? There is an LA version and a Magnum version. The LA version oils through the shaft. The Magnum oils the top end through the pushrods. "Normal" mopar pushrods are not hollow so if you have Magnum RHS X heads (used to be know as "MA-X" then you need hollow pushrods and oil-through lifters.
Also - assuming you "had the usual starting problems"... The cam may be wiped anyhow. The cam is not fed pressurized oil - it has to have oil splashed on it from the crank, and dripped on it throught he valley from the top end oiling. So I would not continue starting it or running it until you determine why it's so noisey.