I agree with Blas's post on the correct (and incorrect) way to install a battery disconnect switch. It's probable most switches are installed as a theft deterrent and not as a true emergency cutoff device.
Since we are also discussing electric fuel pump wiring, I have an engine
oil pressure switch wired in series with the fuel pump toggle switch and fuel pump relay. The toggle switch is 3-position (momentary-on/off/maintained-on). My electric fuel pump feeds a by-pass regulator with a return back to the tank. The momentary-on toggle switch position allows me to circulate fuel (and fill the carb fuel bowls) without cranking the engine.
Given that I have a standard transmission, and if I'm in an accident the engine will stall (unless of course, the clutch is pushed in or I'm in neutral), is there a safety advantage of an inertia switch over my present installation?
Rodger