MAD Wiring with Autometer Voltmeter already installed

Hello,
I have been reading and rereading the MAD article about upgrading your wiring system. I recently had an old alternator rebuilt and it now puts out 80 amps. Being that I have electric fuel pumps, fans and waterpump it is a no brainer to make some adjustments.

I have read the MAD article a few times about by passing the amp meter. Problem is that I already have a volt meter installed in my dash in its place a number of years ago, and the amp meter is long gone. I have been really trying to make sense of this with how my car is set up. Has anyone done this? I do not want to start ripping my dash apart and playing around with thing before I know 100% how to go about it.

Any pointers / diagrams would be appreciated. I have this volt meter if that helps:
2-5/8" VOLTMETER, 8-18V, AIR-CORE, SPORT-COMP

Thank you