ignition
Most Microsoft Windows systems came with a program called "Paint".
Another option is take a digital photo of the paper if you have a digital camara.
There's probably a way to do it with phone pictures too.
Is it dropping from 12.6 to 12.3 Volts with the ignition off? headlights off?
If so, something is on?
The amount of voltage drop depends both resistance and flow.
That's why the headlight test is useful.
Another one is to turn on the heater fan. But current for the heater will flow through the ignition switch. So it will show a poor connection between the main junction and the switch, whereas the headlight test won't.
With key ON, th v. at ign swithch compared to ballast also drops about .5 v. so no doubt there is a problem there. IF this is too much a drop I can drill thru the firewall and go direct.
Are saying when the key is on, Ign 2 at the switch reads 0.5 Volts higher than at ballast?
If so, then narrow it down. For example, see if there drop from Ign 2 to the bulkhead connector?
I wouldn't start drilling holes in the firewall or connectors. Not yet, and not for the ignition wire. Connectors are very handy both for testing and repairs.
Take the connectors apart and see what the terminals look like. Check the wires and the crimps.
So far we haven't proven if the battery feed wire has poor connections or wires. Begin there.
Do it with the lights. The ignition and alternator field should only be drawing a few amps. If there was something wrong where they are drawing more, the ammeter would have shown that.
On the last part I'm a little lost, are you trying to start the engine? Is the starter turning the engine? Nothing will spark if the distributor isn't turning.
My advice is one thing at a time. Find the any bad connections on the battery feed first. Also find if there is a leak - maybe some of the accessories added for pace car useage are still on?
