Update? did you do the XR270 swap? Im curious how it went and if you have any valvetrain noise? I just did mine. XR270 Cam, comp 900-16 lifters, 26120 beehives, Hi-tech pushrods, and 1.72 Magnum roller tips with ARP adjustable studs. Darned thing sounds like a Duramax now....I nailed the pushrod length to the T, the rocker to valve stem contact is dead centered. Everything looks perfect and im confident the adjustment is ok, Im going to get a longer set of plug wires and try to hot-lash it for giggles......Im curious if its a combo of a more aggressive cam lobe and springs that are 155lbs at the seat? Might get some 911-16 springs and remove the dampers and try those out...more like 120lbs at the seat.

Let me know if you did yours and how it sounds

-Ryan