Oil Pressure Sender
This is the NAPA number for the old-style oil pressure sender that is needed to convert a fake gauge into a real working one. For V8 engines, it's also necessary to space it out from the block using common 1/4" plumbing: a 2-4" nipple & a 45° bend. Then the 20-Ohm resistor on the back of the instrument cluster that goes to the pressure gauge must have a jumper wire soldered across it. The cluster shown is for a '94 Crown Vic, but the location of the resistor varies. Don't mess with the 350-Ohm resistor for the ALT lamp, or any others. I used a Wh/R jumper wire to remind me that it's for the oil pressure circuit, which is Wh/R on most Fords.
This pic shows where the sender goes on a smallblock V8, on the L side low on the timing cover:
http://www.supermotors.net/vehicles/registry/media/423345
This pic shows where the sender goes on a modular engine:
http://www.supermotors.net/vehicles/registry/media/192127 
