That monitor circuit could be run with a 20 GA wire- - - - -it carries virtually no current. A 5A fuse should be plenty, and the 18 GA wire will have several times the capacity needed. Just be sure it gets "switched" voltage, not constant.
Jerry


"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!