Car won't start suspect it's in ignition

KitCarlson said
Your ballast is OK. 10V going into ballast, there is a 2V drop between battery, likely at bulk head connector or switch. It may also be possible that the battery is down a cell when cranking. Check battery voltage while cranking.

Also check plugs, if it was running poopy due to choke pull-off failure, the plugs may be glazed.

^^THIS^^ If the voltage is that low with key "in run" then the problem is in connections / bulkhead / ignition switch / switch connector.

I would look up the coil and system at Mallory / MSD. SOME Mallory coils require TWO ballasts---the old one in series with the new one.