oil pressure gauge question

i was wondering where you would hook up the sending unit for an mechinical oil pressure gauge. where is there a pressure port on the engine where you would hook up the sending unit for the gauge? thanks

Im a newbie so my answer might be no help at all... is a mechanical oil pressure gauge a different kind than the one in there. cuz i just replaced mine a month ago and i can tell you where the one i replaced is, but if the one ur putting in goes somewhere else im not sure. let me know...... also if your trying to put a new one in becuase your pressure gauge is telling you weird things, idk if i would change it cuz thats what mine was doing and after a brand new gauge it still is all messed up.