Pushrod oiling/heat?

The rockers for Mopars with the best oiling to the pushrods are the Comp Ultra Pro Magnums, T&D, PRW steel(which are a copy of the Comp).

Those have the oil feed hole to the pushrod within the groove, and the oil is fed to the pushrod via a thru-hole in the adjuster screw itself.
Direct feed..... not splash.

But....... if there is excessive leakage around where the shafts mount...... you could still have problems.

The down side of the rockers with needle bearings in them is there is a lot of leakage thru the bearings themselves.