Am I missing something here? If the damper is set at zero, the #1 piston will surely be at the very top of the cylinder, but it could be the top of the exhaust stroke as well. Just lining the damper at zero and seeing that the piston is at the top of the cylinder will not ensure you are at the top of the compression stroke since the crank turns twice for each time the cam turns once. Maybe I misunderstood what you meant.