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today it was dead steady needle, just negative all the way to work, then pegged in the positive all the way back.

You have an open most likely in the field circuit (since the alt/brushes are new), it went open on the way to work hence the discharge (negative) then the open connected later when you (re)started up & came home so it was charging (positive) a fair amt to charge the batt back up. I'd start w clean the ign1 circuit (blue) wire on each respective brass terminal on the bulkhead/check reg is grounded well/any loose connections in the blue and green field circuit(s)

live every 24 hour block of time like it's your last day on earth