Hi I just purchased a 1951 model 200 that had been restored about twenty years ago. I am just starting the TLC to get her running properly again. I believe that the engine had been rebuilt into a 327 ci. I noticed that the engine number starts with an H. Does that mean it has hydrolic lifters? Anyway I want to service the air cleaner, and I have not tried too hard to separate the upper and lower halves as I didn't know anything about it until I read these post. thank you very much! I was taught to never force something unless I know for sure that it had to be. Is the screw on the side of the air cleaner to drain out the oil before separation? I don't feel any slosh when I wiggle the air cleaner so I am thinking that there isn't any oil in it now. Should I get a friend to help me pull the halves about? Thanks for any suggestions