Thanks to Roger Lee... I made a quick oil pressure gauge. I used a flexible water line with 3/8NPT threads that was about 12' long. The hose proved to be really cool since it was very flexible and I was able to take it right into the cockpit and compare values. Certainly not the least expensive option but given the value of the results, well worth the price. I also purchased a "Rainbird" pressure gauge for 10.00 at Home Depot (the only one they had), and a couple of brass fittings.