In the pursuit to resolve the excess oil pressure concern, Lee Teicheira and Bill Lawrence researched the concern, located the location of the oil pressure relief valves on the underside of the engine case, fabricated a tool to remove the relief valve caps, removed the caps and the pressure valve springs and determined that the relief valve pistons were stuck in the bore. Lee used a 12 mm thread tap to engage the open end of the piston and, with significant effort, was able to free both pistons. After cleaning and polishing both pistons and determining that they moved freely in the bore, they were, according to the engine assembly instructions, lubed and reinserted along with the springs and caps. All set to go forward with rechecking for proper oil pressure.