What if the lines were wrapped around for a short distance about halfway throught the truck for preheating. If it the WVO gets too hot it could have some time to cool before a Vegtherm at the injectors. Could that work? If there is no answer to this question, this summer I might do an experiment with a fuel pump, temp. gauge, and some oil. To me it seems like using exhaust and electric heaters would be easier than coolant. Also another idea, running a pump and alternate WVO lines to circulate the WVO from the tank around the exhaust as a means of preheating the tank. Have a temp gauge in the tank to know when to engage the pump to the exhaust for preheating the tank. Just an idea that came to mind. Thanks.