go for it. propane is really reliable and also keep in mind it is 110+ octane so you will have to play with your timing
also propane is normally stored at high pressure, so most of the propane has turned into liquid. When the propane comes out of the tank as a vapor it absorbs a tremendous amount of heat. It gets super cold by the time it gets to the propane carb. This is why it has to go through a heater in the regulator/mixer/etc. This is why the hot water out of the motor is used to fully vaporize the gas and to prevent icing up of the intake at the propane carb - otherwise the vapor would freeze water out of the air coming into the motor and quickly clog up the intake. So, I'd have to disagree about the lower temperature thermostat, you need as much heat in the motor as possible (plus a propane motor becomes more efficient at higher temperature).
So... any thoughts on a distributor I should use?
one of the upsides of propane is it has less carbon molecules in it than gasoline. Carbon is what turns oil black and condenses into sludge. Consequently, oil in propane motors stays VERY clean, and propane motors wear much less than gasoline motors do.
The one side effect of the "clean fuel" on propane motors is that the valves tend to burn up quickly (stock valves and seats) because propane doesn't provide lubrication to the valve and valve seats like gasoline does. This can often be taken care of by installing hardened seats and hi-temp exhaust valves. Even the "unleaded" motors that came with hardened seats (since 73-ish) still have trouble with valves using propane fuel, so it is usually necessary to install something like Stellite seats in the exhaust to keep the seats from receding. Intakes do not need hardened seats because they are cooled and somewhat lubed by the incoming intake charge.