'68 Barracuda - charging system questions

Battery charged to about 12.5. Started up and shows 8V at blue wire. Just the 12.5 showing on battery terminal. Alt BAT stud still pegging needle at 16V+. WIll put in the ammeter bypass wire and see what changes...
My advice is:
(a)look at the ammeter and see what it shows you.
(b) Backprobe the bulkhead connector on both sides of the alternator feed.
(c) check the voltage at the bulkehad ignition wire cavity.

Based on what you've found the ammeter is not likely involved in the problems. So based on the information so far, bypassing it at the meter will simply remove a usefull tool
Bypassing the ammeter on the engine compartment side can increase the current trying to get through the existing problem spots.

This diagram is pretty close to your '68 Barracuda.
Ignition wire's may or may not have the white stripe, and the power feed to the key switch may red.
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