For hooking up a Volt/Amp monitor system the easiest is by the power panel.
I just took a knife and did cut out the square openings (tight) and installed the 12 volt and 120 volt monitor system at eye height. The shunt spools for amp readings slip over the wires one from the battery 12 V and one from the 120 V supply. They are all in the Power Panel. My 12 volt system has a red display (more critical) and 120 volt blue display.
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