well I'm pretty sure I can get a large tank... how much does one of the small tanks used for bbq's hold?  5gal?  I'm think'n the tank/tanks i might have a line on are 15-20gal.... 

Toyo478... what's your friend get for milage?  and what's his range?  (also what's his tank size?)

stocker... the tanks I'm getting I'll make sure they're removeable... so i don't think I'll have a problem with them filling them up... I'll just unhook the tank, take it out... fill it up and throw it back in...  hummmm...