warm engine

wire throttle FULLY open, that'll shut off any fuel supply as the fuel won't flow unless there is air passing thru the carb, which it won't be at cranking speed, which is also how you start a flooded engine.

by the time you remove all the plugs, the engine will be cool enough

spin the motor over a FEW times, that'll spit out any fuel in the system -intake, carb passageways, head passageways, combustion chamber.

screw in the gauge and go for it.

crank a minimum of 3 revolutions

don't worry about any spark, as there won't be any fuel there, just don't touch any wires while doing the test, as in holding the gauge too close to a wire. If you really want to, then just pull the coil wire from the coil.

Oh, and there won't even be any sparks if you don't use the ignition key to crank over the engine, that is what a remote starter switch is for. Buy one, or make one using a push button momentary switch from the hardware store, been there, done both, have both.