That is about right.

12v to 6v Runtz-style gas gauge resistor

12v to 6v heavy duty resistor for the heater motor (it will get hot)

Ballast resistor on the power side of the coil, unless the coil as that resistor built in.
http://www.chevsofthe40s.com/detail/5999/Chevrolet_Ballast_Resistor_For_12v_System.html