5.2 Magnum Question

I'm pulling a 5.2 Magnum to install in my 71 Demon project it has a ticking lifter in the area of #6 cylinder. It has good compression and burns no oil. The lifter starts making noise when the oil pressure drops below 30lbs. No noise at 40 lbs. I am thinking it's the dual roller lifter stamped metal assembly. Any input would be appreciated. Truck performs great otherwise. Only 120k miles.