Bulkhead bypass vs ammeter bypass
The Magnum V-8 engines ran a thick wire (~8 awg) from the alternator output to BAT+, across the timing cover, so you could do that. I took that cable from a junkyard one (Grand Cherokee or Dodge truck) for my 1965. Mine doesn't run directly to BAT+, but near it. It runs to a back-back power diode on BAT+ which breaks down in forward bias ~0.7 V drop to shunt the alt current to BAT+ as the ammeter reaches its limit (around that voltage drop). I posted PN's and photos ~15 yrs ago.