[dsraven]

the sensor on the oil pan is likely connected to that oil cooler block off plate. you could easily install a "T" fitting there and run the sensor and the oil line to the manual guage. like said, use a copper line from there up to the guage or at least past the engine and exhaust heat. I know a nice stainless braid hose looks great under the hood but they are usually teflon or plastic/nylon tubing inside the braid. not that great with high heat. make sure to use some clamps on the tubing to keep it from vibrating because the copper can develop cracks next to the fittings from work hardening of the copper.
I have often thought a small manual guage installed in the glove box temporarily (or not) or somewhere out of sight would be good to have for situations like this. if you have a low oil pressure indicated on the cluster you could simply open the glove box for a look at reality the old fashioned way, analog.
keep us posted on how it all works out