Id agree with that guy Mac Mac. The modified oil pumps have a slight modification to the relief plunger which was prone to stick, Although mine never did after 120 thousand miles. Another issue is the screws on the pump backing plate coming loose which can cause leaks and pressure drop at high RPM. Its worth doing for peace of mind at around 80 thousand miles IMO or at least check the bolts and tight. Id replace it though.
Damo