Inertia vs Oil Pressure Switch

I have used the OP switch for the last 25-odd years on various vehicles. Have one on my '65 Valiant, installed as described below. A pic or two in my sig linked build.

An OE application, if they're still available (Couldn't find it on Rock Auto) is one for a Chebby Vega. They had electric pumps and GM used such a switch to protect against fires.

You are correct, you still need a sender or switch for what ever is in the dash. What I do is mount a 1/4" NPT "T" to some place convenient (fenderwell, firewall, etc.) and put both sensor/switches there. Then I run an 1/8" copper tube from the sender/switch port on the engine to the last port in the "T". Be sure to leave a loop or some considerable extra length for vibration induced fatigue relief.

One vehicle I wired using this switch had only that switch to turn on and off the fuel pump. Worked great, about the time that the driver closed and locked the door after a long drive the pump would quit.