I know there is a certain procedure for that but I just spin the motor over until
the intake valve closes. You will be on the power stroke and both valves will be closed. The stock specs for valve adjustment are .013" for the intake and .021" for the exhaust. These should be set hot but should get you started and then you can readjust them after the engine warms up. These specs are for a 1966- HP273 with a solid lifter cam by the way. I got the info from a factory service manual. Good luck! toolmanmike