WE NEED to know the year/ make model, or to put this more pointedly "IS THIS" a 74? (Seat belt interlock)
You may have gotten the shift mechanism / linkage from the column down out of adjustment when pulling the dash, OR IS THIS a console shift?
If this is NOT a 74, the electrical path for the starter relay is key switch---harness connector---through the bulkhead connector--to the starter relay coil--through it and out onto the wire leading to neutral safety at transmission---and to ground in park or neutral
Then once the starter relay is engaged, the contacts close and send power from the "big square" screw on the starter relay down to the starter solenoid
DO YOU have a factory service manual? Go to MyMopar and download one, free. You may have to settle for Dodge / vs Plymouth, etc