Dean and Gerald,
I would use a low oil pressure switch, one that loses ground when the oil
pressure goes low. Using a 12V Solenoid Relay from an electric golf cart
(like a ford starter relay, except rated continuos duty) Run the 12VDC line
from the truck battery to the solenoid, then to the bargeman
connector. supply 12VDC to the coil of the relay, and run the ground to
the low oil switch.
Mike
Mike and Marianne Keith
75 Argosy 26' 81 F100
New Florence, MO
GR8R STL unit #4503