On my Yanmar 2GM there are two zincs, one on the Stbd. side and one on the rear of the engine. In the process of replacing them I can get the rear one off, but cannot remove the Stbd. side one. Have removed everthing from the engine to give access but still haven't room enough to give leverage to break it loose. Any ideas? Also since I have replaced one of the zincs can I let it go at that. Thanks