Thank you everyone for all of the advice. Unfortunately work is really busy right now ant the truck is just sitting in the garage. Bypassing the heater all together was my first thought, and probably will still do that for the short term. Hopefully I will be able to fix this by the end of next month.

magnum440d100 Thanks for the offer, I am tempted to take you up on it, but would not be able to get out there for a few weeks.