Pardon my lack of knowledge but I've been away from Y blocks a long time and bought this car with a 272 (supposedly rebuilt) last year. The car is using a quart of oil every few hundred miles. Recently when pointing the nose of the car down on a steep driveway a puff of blue smoke belched from the right side exhaust. I checked the exhaust and get an oily smudge from the right side, but the left is clean. So I figure a head drain is plugged, pulled the valve cover and everything is clean as you would expect on a rebuilt engine. I did notice two things: There is a drain/overflow tube from only one rocker stand on each side, and it is directed at the pushrod hole. It seems as If I remember there should be one on each end rocker stand, and it should point to the drain hole. Oh, I pulled all the spark plugs on that side and three have light grey tips and one is brown (front plug). I would expect black oily tips with it using this much oil. Any advice, comments, or things to check will be greatly appreciated.