Ignition Circuit Voltage Drop…where to from here?

Hmm... that looks nice! I'd keep the same gauge or only one step larger; the wire is not usually the issue; the connections and crimps on the wire ends are.

Thanks for the tip!
You're right, I think What I actually read/saw was people using a large gauge for the alternator output to starter relay connection (8 gauge I believe) ... Not a larger gauge for the VR connection. 👍🏽