I have a mid to late 80's Honda BF75 7.5hp that's a short shaft and has only been used in freshwater. It has maybe 50 hours tops on it and has a new water pump impeller, engine oil change, lower unit lube changed, and new spark plugs. It will usually start on the 2nd or 3rd pull when it's cold and runs great however I need to get a long shaft for my boat. What should I ask for the motor?