Thanks for the information, I will try giving them a call. My truck does have recirculating block heater on it already, but that factory air heater is a quite a conversation piece. Its so much different than modern glow plugs or grid heaters, and very few people have heard of a system like it. I will try to get a few more comments on here so that I'm not being moderated anymore.
Were the Gas powered 450 Tandems more common? I would assume that they would have the same transmissions/differential set up as the diesels.
We have the little jimmy running quite well now, and it sure is fun to drive with the twin sticks. I can wait to get a hitch setup on it and starting pulling with it.