'66 Barracuda starts then dies right away

See My post on "Double Bypass". Mine wouldn't stay running either, 66 B-Cuda.
barracudadave67

I've already done the mod where you run a wire to the starter solenoid to relieve voltage to the ammeter (path of least resistance). This has been a quickly deteriorating condition. First started last week when moved the car to the end of the driveway and it just died. Then I took a test drive around the block and next day and it died 3 times. Made it home though. Now it just won't staying running after I turn the key to run position. Feels like it might be the ignition switch. Seems like if it the bulkhead connector or the ammeter failed it wouldn't start at all.