I am trying to bleed the cylinders on my tilt and trim on a 1979 mercury 90 hp the cylinders has 4 screws 2 on top one is an alen screw and the other is a flat head, i have two on the side were my lines come in the allen screw on the side has a fatter hose coming into it and the flat head screw has skinner line going to it. I know i have to take the cylinders off to do this but i don't know if i have to position the shaft in a certain position or what screws to bleed please help

