Coil feed wire

I got my 49 engine back together and no start. Began tracing things, and had 6 volts at the coil feed wire but not enough current to hardly make a spark to the block, and barely enough to cause the coil to make spark enough to see in the dark.



I hot wired the coil from the battery and the coil threw a huge spark from the coil wire. Plugged it in the cap and nothing from the plug wires. I wire brushed the rotor that looked brassy and brightened it up. It started immediately.



Wiring diagram shows this wire coming from the 'p' terminal of the light switch, where its siamesed with the wire that lights the ignition switch.



I could get little or no voltage at the switch terminal, so figured I have a bad light switch, and ran a new wire from the ignition switch to the coil, which works fine. And now the ignition light works.



Drivin me nuts...any ideas?