I was in Northren tool getting some parts and saw they have tanks used for spary chemicals that mount on a ATV. Might this be used as a secound tank? Does anyone use a electric fuel pump to push the WVO from the tank to the motor? Does anyone sell just the tank?

That sounds interesting. I have seen sprayer tanks a lot out here and never thought about that. Should be chemical resistant and semi-easy to insulate.

They have these at Harbor Freight too I think.

So far the cheapest thing I have seen that may make a perfect WVO tank is the portable RV sewage tanks. do a google search for "RV portable holding tank" and you might come up with some info.