Did they ever use different fuel tanks (instead of the 50 gallon single tank) on some deuce models? Like a couple of 55 gallon tanks for the tractor version, for example? I forget which truck uses two 55 gallon tanks, is it the 800 series wrecker, or tractor? Anyway, I do not believe it is possible to mount one of those 55 gallon tanks in place of the existing 50 gallon deuce tank. as the 55 gallon tank has different dimension, and is more cube shaped than the elongated deuce 50 gallon tank.