65 heater wiring

[roan65]

A little background..
I rebuilt/restored my 65 about 15 years ago in high school untill funds ran low, and some things got over looked. Now they are biting me in the butt...

My problem is with the heater wiring. My stock unit DOES NOT have the rheostat on the box. However if memory serves me correct I switched out the heater control switch to the rheostat style. I now have the rheostat heater box that I would like to put in(at least I think that is what I want to do). However I am a little confused. The heater control switch looks like it has only one plug that plugs onto the rheostat. I would think there needs to be another wire in there that has to go to the motor itself. In the engine compartment I have the 2 wires that go to the fan.

What am I missing here? Anyone have a wiring diagram?
how do I convert a non-rheostat setup to a rheostat setup? What is the differance between the 2 systems?

 

[Tim65GT]

I couldn't find a wiring diagram for a heater with rheostat (didn't know it was an option)

Here is a very simplified diagram of a typical heater. I would assume the rheostat would be wired in as such:
(dotted line)

 

[roan65]

Sorry, one of the parts catalogs was calling it a rheostat. While doing more research with the online catalogs everyone calls it a resistor. Sorry for the confusion.

My heater switch only has i plug in to go to the resistor nothng else. What it appears is that mine was a 2 speed motor and the ones with the resistor are 3 speed. Is this correct? So do I need the 2 wire motor or the 3 wire motor?