nice screen name, deftones are one of my favorites, it is normal to have oil in the stator housing. It sounds like you engine was swapped out at one time, the F models serial numbers start with CB750FE , sounds like you have a K engine. if you go to the main page of this site there is info on all the SOHC models serial #'s ect ect. The air filter housing on most models says CB750 F so its easy for people to see that and think it's an F.....
rock on,
Gt