I have a 1968 Merc 200. I got the motor running well but never realized it would not turn, it is froze up pretty good. Wont take any grease at all. I have pulled the cert and it is really gummed up in there. Can anyone tell me how to fix this without having to pull the powerhead. I think if I pull the top part of the shift linkage I can and pull the whole powerhead, pan, and midsection free and just have the transom mount and turning yolk. Which would let me separate and clean it. I hope it works this way or if anybody else knows an easier way.