It depends on how a lot of things were wired. The use of relays etc.
OEM used 3 separate feeds to start the car.
Feed #1 (IGN 1) feeds the coil during run conditions thru the ballast resister.
Feed #2 (IGN 2)bypasses the ballast resister to feed full battery voltage to the coil
Feed #3 (Start) triggers the starter relay to connect the battery to the starter.
Some of the ballast resister and wiring might be redundant due to aftermarket ignition.