Okay, on the aux heat.... I liek the Espar unit myself, for its simplicity, etc.. but, the cost.... no thanks. If you can figure out a way to heat the coolant, with a seperate heat unit like that, make 2.. .I will buy one from ya....
AS far as the gelling... for number one, its just a blend of #2 and kerosene. To lower the cloud and pour points..... most cold climates start selling it late in fall, right before temps get to freezing...
NOW, a simple forced air unit, could be made with a heater core as you know, and just plumbed from the coolant.. I would use copper tube to the rear, to prevent stuff kicking up and ruining anything... And a nice decent quiet fan... mount it all in a box.. and you will have plenty of heat.
The trick, would be a ciruclating pump(not a full on water pump), and regulating the flow past the t-stat... heat the coolant to 120-150*, would be plenty.
You get get a valve, that opens when the heat unit is tuned on, bypassing the t-stat... this way, the motor is always warm as well.....Man, I cant tell you how many times I fired that truck up, and drove 10-14miles in the sub zero temps before heat would come on....
I think your on to something. You thinking of maybe mounting this unit... on the ceiling, up front in the cap?
For what its worth, I am in the HVAC field(needed to find a civilian trade), and will help as much as you want(I love working with oil burners as well)...
Chase
