If you are installing your distributor you will also need to make sure that you are at TDC on the compression stroke and not the exhaust stroke.I usually pull a valve cover and watch the rocker arms on the number 1 cylinder.The TDC following when the intake valve closes as you turn the motor clockwise is what you need.If you have reason to believe the pointer or marks on your balancer might be off, you can verify them fairly easy.Take an old sparkplug and gut it.Place a bolt through the middle that sticks out a couple of inches and secure it in place by welding it or some other means.Smooth off any sharp edges and thread it into the number one spark plug hole.Gently turn the motor clockwise until the bolt just touches the piston and put a mark on the balancer where the pointer is.Turn the motor counter-clockwise and do the same.TDC will be exactly in the middle of the two marks.