question on gauge swap from dummy lights

[bh86]

im swapping out the dummy light gauges to normal gauges and I have most everything figured out except for how to wire the charge indicator differently. i've read a few threads on it and from what I gather it seems that the brown wire that runs from the alternator to the battery indicator light for the dummy lights instead would run to an ignition hot in run and start with a resistor or something along those lines? any help would be appreciated most of the diagrams I've seen don't seem too clear on this part.