I'm also curious about the propane tanks, and the conversion. I wonder if its worth-while to do. Seems like it was to them, since its installed on a new crate motor.
You can see the tanks and the filler caps in this pic just below the bumper:
Many people heat their houses on propane and he may have a tap into that to fill up his truck (though that's probably not legal in the states, I believe they want to tax you on the fuel if it's used on the road).
Propane is awesome because it keeps the oil super clean and will completely vaporize at basically any temperature we come across. Unlike a carburetor or even fuel injection, there is really no chance of raw fuel contacting the rings at start-up/cold temps which is the biggest wear factor on a motor.
Propane also has the advantage of being ridiculously simple, more so than even a carbureted engine.
Downfalls are that fuel is a bit tougher to come by, not really tough to come by but not as easy. It doesn't contain as much energy per volume as gasoline, though on many motors it will make as much or more power. Theory says that propane has less energy per volume (which it does) but it's also a vapor under almost every condition, which gasoline is not.
One thing that has chapped my ass about filling up propane is that "only certain people can fill it". Often that means that after five, on weekends or when they are on vacation the people that are actually there working can't fill your propane tank.
At midnight, you can drive up and fill up your tank with gas with a credit card. If you need propane, you need to wait until someone "qualified" is there, which is definitely going to be 9 to 5 if you're lucky.
I know at Blazer Bash last year I was told the only guy qualified to fill propane tanks at Slickrock Campground (where a lot of the Blazer Bash people camp) was on vacation for two weeks and they couldn't fill any propane tanks until he got back. They probably had 1000 gallons sitting there.
