Ballast resistor and map light

[my68barracuda]

cleaning up the wiring on the 68 Barracuda.
Two questions:
1) I had eliminated the ballast resistor some time ago by a jumper across the resistor terminals. Used the existing coil wire to trigger the MSD box. In process of cleaning up the wiring.
At the ballast resistor terminals is a brown wire, goes to J3 Ingition switch 2
And a dark blue with tracer wire to J2 ignition.
Am I correct in thinking the J3 brown wire is start and the J2 dark blue/ tracer is run?
Guess I will need to tie both together to activate the MSD box or is there a work around to only keep one wire from the ignition switch?
Question 2:
The Barracuda has a Map Light switch, lower left side of the dash,
But what does that activate?
I have a glove box light and the two inside rear lights. No dome light.

 

[Frank Mopar]

You can run MSD through the ballast. It gets its power from the other 12v wire.

 

[Mike69cuda]

The map light switch turned on lights under the dash as I recall.

 

[Donnie514]

Well mine turns on lights under the dash at kick panel but only when the door is open. How dumb is that. You must supposed to look at your map down at your knees while driving down the road with the door open. Thank God they invented the GPS. I think if you do not have a padded dash the light was supposed to be above the heater controls facing down wards.