Just changed the impeller, but before I put it back on I am going to get the oil so there is NO WAY I forget to put it back in.. I understand it has to be put back together first, but not sure how to fill it? I think I saw somewhere there is a tool for it? Anyway to do without tool? Also what weight? I looked it up and saw 80w90, is that right? and about 1 2/3 quarts? Its a MC1 outdrive. Thanks