One wire GM style alternator wiring help needed.

For cars that sit a lot, a GM one wire alternator will drain the battery in about a month. They pull about 75 micro amps all the time. Doesn’t sound like much, but it is enough to drain a battery over a period of time. Found this out on my boat with a chevy engine. A cutoff switch would help this, or you could just disconnect the battery when not driving foe awhile.