Not sure how applicable this might be but I installed a couple of electric heaters (ni-chrome wires) on my fuel lines and am pleased with the results. Used the Fatty Wagon kit for the big fuel filter. Was concerned about putting heat on the pre-filter, so I replaced the fuel line about 8" before the pre-filter. Wrapped that metal portion of the line with heat wire. Both heaters reach about 200 degrees F. Of course the fuel doesn't get that hot, as it's just passing through. I use this setup for running bio, but have run D2 through this heat and it has done well.

__________________
John Schroader
bio burnin' 83 300D, '83 300 SD, '79 240D
"I've never met a man who was good at making excuses who was good at anything else" Ben Franklin
"You cannot permanently help a man by doing for him what he could and should do for himself" Abraham Lincoln