Post #3 on the following thread shows the Fiero motor in mine. I left the tube on there and just pointed it downward. I don't know where it connected in the original installation, I assumed it acts as a vent so thought it might be better to leave it open.
I'm using a Camaro resistor just because it cost half as much. It is identical to the stock truck resistor other than it is attached by screws instead of snapping place. If I had it to do over I would have spent the additional couple of bucks for the convenience of snapping a stock version in place. In any event it works perfectly with either the original motor or the new permanent magnet type.
http://67-72chevytrucks.com/vboard/s...ghlight=heater
I also prefer the econo heater. When I had a deluxe heater the cab always smelled like antifreeze, in spite of a complete heater rebuild with all new seals, core, and no leakage. I also got tired of the inconvenience of having a breadbox hanging on the firewall.