As neat of an idea running LP is, there is no real need to. Also you have to take into consideration of where the LP Tank is going to be mounted for safety purposes.
What advantage do you have for running LP over Gasoline? You do have a cleaner exhaust, but that is best for Indoor use. You might get lucky to have a lower cost of fuel over time as well, but for the cost of the kit not counting installation, it's going to take a while to recover from it
Just things to think about.