I drain the oil for the lower unit and is white I need to know how to open the lower unit on this motor to replace the seals and o-rings, I have the seals kit and I don't know if I need special tools. I took the propeler out and I see 4 screws inside and also see the screws that hold the unit to the uper part, I also have a repair book but doesn't specified how to take it a part if some can give me some tips I will be able to work on it. TKS