I have a new to me 1990, Ericson 38-200 (El Sueno) with M5432 engine. Currently on Lake Champlain, I plan to sail to NH Seacoast next Spring. As I prepare to winterize, I decided to replace the zincs in the heat exchanger, so I’m ready for move to salt water. What I thought were zincs on either side of heat exchanger, turned out to be only plugs, which was probably okay for fresh water. I did get zincs from the local Universal distributor, but they don’t go any further than maybe a half inch before hitting stop (I’m assuming hitting against fins in heat exchanger). Has anyone replaced the heat exchanger zincs?What are your experiences?