Burning red dyed off road diesel in a vehicle used on the road is a pretty big risk. One thing our government takes Very Seriously is collection of taxes. The fine is enormous.
I have heard of farmers running two tanks, but I think the tax collectors have probably thought of that too.
Consider that if the fuel system recirculates unused fuel back to the tank, when you switch between tanks, dyed fuel would be pumped into the other tank. It takes about five tanks of fuel to flush out the dyed fuel.
I have wondered about this in considering using WMO in a separate tank to fuel my deuce.
If I start the deuce on straight diesel, run it on WMO from a separate tank, and cool it down on straight diesel to flush the lines for easier starting, will WMO get pumped back to the diesel tank?
Does the unused fuel get recirculated to the tank or not?