I was advised by a wise restorer that the best way to determine if the number 1 piston was on the compression stroke was to remove the plug, put your thumb over the hole and turn the crank until you felt the pressure. This works well if there are two of you. One to turn the crank and the other to hold his thumb over the hole. But I'm always working on my cars alone so I needed an extra hand. I found one: take a piece of half inch pipe, cover one end with a latex glove, fasten it with a rubber band and screw it in. Viola! You have an extra hand!