Headlight Switch Cranks Engine??

Oh ok, thanks. So voltmeter to yellow wire, turn on headlites, see if voltage jumps to 12 volts.
Gary: Are you trying to solve your problem or Manny's (the OP)?
Be easier to do these one at a time - even seperate threads would be good.
Its almost a given one of Manny's headlight wires is contacting the start wire to the relay, especially if it only happens when the headlight switch causes the starter to turn when the headlights are on. If it happens when parking lights are on, then its a wire in that circuit (or instrument illumination).

Do yourself a favor and download the Dodge Service manual for your year. Then you'll have the best reference for colors etc. It still may have mistakes but less than the non-factory diagrams like those on mymopar.

For your problems with the signal and marker lamps take a look at the guidance from Tech. Using the FSM wiring diagrams, make a schematic - it may be the same as one of those shown in the Master Tech booklets, but it may be a little different.

1973 Chrysler Electrical System, Master Technician's Service Conference 310
1973 Chrysler Electrical Circuit Troubleshooting Reference, Master Technician's Service Conference 311
1967 Fuse Failures that are Tricky

Another situation to be careful with is when the switch is located in the ground wire. This is much earlier the 1972 but would still apply to some circuits.
Automotive Electricity (Session 118) Dome Light Switches