Boarder Line Low Oil Pressure

My son and I rebuilt my 340 several years ago and oil pressure was fine, but a few months later the pressure started dropping, I thought oh **** what did I screw up. I tried 20w50, no help so I was going to tear down the engine luckily, I dropped the trans and pulled the torque convertor and noticed oil weeping from the cam plug I cleaned around the perimeter, got out the JB Weld and problem solved and have great pressure ever since. Goes to show, you never know until you start poking around!