Well, I guess I can forget about 100% of everyone on the Stovebolt doing this! But for all the rest of you, here is the schematic so far. You can purchase the parts on Ebay or usually Amazon has most of it.
http://www.devestechnet.com/Images/Oil%20Pressure%20Alt%20Warning%20Schematic.jpgFor the cost of a Piezo Buzzer (I got the two tone version that puts out 105 db), a Bosch Style 5 pin relay, an oil pressure sensor (you can get a 1/8" NPT Tee so you can keep your old gauge), Light Socket and bulb you are good to go.
I am working on a delay circuit to keep the buzzer silent between engine on and the time it takes for the oil pump to get past 6psi. It's a second maybe, but still annoying. I also think maybe a 10 amp fuse to protect the circuit from another system in the truck causing a fault. I'll post anything new here as I get it figured out. I think there is about $40 in parts at most. The sensor is the expensive item.
To install it, you will need to find the Alternators R1 Terminal to Ignition wire (it's the alternator warn light wire) and run a new wire to the electric oil pressure sensor.
Anyone with any knowledge of how to delay the buzzer about 5 seconds to be safe, let me know. I will have a complete parts list with prices and everything as soon as I make sure of my sourcing.
