The anode on my 120se saildrive only just lasts the year out between changes ,I have a galvanic isolator and the boat is rarely in marinas. I also have a peardrop shape anode fitted from new attached to the engine, it has eroded VERY little . My feeling is to sever the engine connection and reconnect to the saildrive, the anode is close to the saildrive just aft of it . Any thoughts out there ?? Geoff