Hello. I have a few questions about my lower unit and gear case group. First, my driveshaft takes a pin and not a key,but the impeller looks like it was made to accept a key ? Also, is the seal below the impeller / plate ( that accepts the driveshaft ) supposed to turn or does the driveshaft just turn inside the seal ? Any recommendations on a specific grease to use ? And last, is there supposed to be some sort of gasket or seal between the gear case unit and the lower unit ? Thanks in advance. ( I tried posting this yesterday, don't believe it went through ).