Balast resistor or no?

The "usual problem" with eliminating the ballast is that you somehow don't get the bypass wire connected. What you need to do either physically, but certainly electrically, is to connect the two ballast wires, then use the old coil+ wire to feed the new system

HOW AND WHY

The ballast receives power with the key in "run" from what is called IGN1 from the key. THIS GOES DEAD when cranking the starter.

Power for start to the igntion comes from the bypass cirucuit, IGN2. This is ONLY hot during cranking, comes from a dedicated contact in the igntiion switch and feeds the coil+ side of the ballast (usually brown)