I forgot to address one part of your question:
"also if i understand this correctly i will no longer need the resister wiring on the ignition switch?"
Heres the deal:
A) If theres a resistor (often an open spiral coil of bigger wire) on the switch used to control Bright or Dim lights?? THAT IS STILL USED FOR BRIGHT OR DIM LIGHT CONTROL IF THE SWITCH IS SO EQUIPPED (Sorry I dont have any M's to look at and cant recall if they had a dim/bright light switch)
B) If theres a flat wound coil of smaller wire, thats more likely the Low/High Field control resistor used to regulate charge to High (resistor by passed) or Low (resistor in series with terminal to FLD on genny) AND WITH A VOLTAGE REGULATOR NONE OF THAT OR THE WIRE FROM THERE DOWN TO THE GENNY WILL BE USED
A typical low high charge control resistor is flat wound and may be like 2 to 4 ohms and it will have continuity in the terminal that wires to FLD on genny to the case ground. In LOW the terminal that goes from the switch down to genny would be around 2 to 4 ohms but in HIGH it should be near 0 ohms from that terminal to case ground.
A typical lighting dim/bright resistor is much less in ohms and is heavier wire and is in the circuit that leads to the lights
You DID NOT mention 12 volt conversion or any ignition ballast resistor so if you have such and have questiosn post back. Originally it was 6 volts and a 6 volt coil so theres no external ignition ballast resistor. if its 12 volts you need either a 12 volt coil or the old 6 volt PLUS an ignition ballast BUT NONE OF THAT HAS TO DO WITH LIGHT OR CHARGE CONTROL RESISTORS ALREADY ON THE SWITCH
Now this plus my post below should answer your questions