Everything was going so good
When the car is running, what does the ammeter show?
Then when the key is off but the engine is still running, what does it show?
While its running with the key off, also do some voltage checks at various locations in the feeds and ignition circuit. This, together with the ammeter may help narrow down where the power is coming from.
I'd probably check the easy locations first.
These with the ammeter will be clues to
a) whether the alternator or the battery is providing power that is keeping it running.
b) whether the current is getting the ignition from the ignition run (J2) or ignition start (J3) circuits.
After that I'd probably be looking at the buzzer wiring.
Also you mentioned pressing on the ballast resistor connection produced a change.
I'd pop the covers off of both connectors to look at the wire terminals.
When the car is running, what does the ammeter show?
Then when the key is off but the engine is still running, what does it show?
While its running with the key off, also do some voltage checks at various locations in the feeds and ignition circuit. This, together with the ammeter may help narrow down where the power is coming from.
I'd probably check the easy locations first.
These with the ammeter will be clues to
a) whether the alternator or the battery is providing power that is keeping it running.
b) whether the current is getting the ignition from the ignition run (J2) or ignition start (J3) circuits.
After that I'd probably be looking at the buzzer wiring.
Also you mentioned pressing on the ballast resistor connection produced a change.
I'd pop the covers off of both connectors to look at the wire terminals.