All true, however..........they want it done immediately. There is no source for said breaker or surface mount within 100 miles of where I'm sitting. I can order it on line and have it shipped, but there is that work thing going on that allows me to go boating. There are boat mechanics around here but no electricians. Blue Sea's makes the project sound like a slam dunk for DIY but it is at the very upper edge of my ability because I don't understand the technology. There is already currently a breaker mounted in the aft cabin where shore power enters into the boat, I don't know if the ELCI is in place of or in addition to.