Classic/Antique Car Repair: oil pressure gauge, oil pressure gauge, gage

Question
I have a 1974 Corvette with electric oil pressure gauge the needle stays at 80 psi., with engine running or shut off. Is there a way to check the gauge is bad or if it is the sending unit that is bad.  Thank You

Answer
with the key off the sender would be out of the loop. Sounds like the needle is stuck. To be sure remove the wire to the sender and start the engine. If the gage goes to zero then the gage is working. My bet is thast it will stay up and indicate a bad gage.
Brad