Just to be clearer,
Nitromethane is not the same as calling GlowFuel "Nitro"

GlowFuel that we use with glowplugs is Methanol (+oil+nitromethane)
You can mix glowfuel with gasoline to run without the heavy spark stuff, it is the Methanol that makes the Glowplug do its thing.

I'm no guru, but the sweet mix I see folks using is
2parts gasoline + 1part 'RCCar'GlowFuel(10%oil10%Nitro)
in gasoline engines(weedies) with a glow plug in a plug adptor, if you tune the carb rich enough.

Side benefit for this boat use is that the glow will run a cooler engine than gasoline.