QUOTE
You time the engine through that hole.
I believe he is yanking your chain. You dont time the engine through there.
However there IS another hole where you can see the TDC mark on the flywheel just above that hole where the case meets the engine case (at 12 oclock)
I believe that it's purpose is for a clutch inspection or measurement.
Perhaps there is a way to measure how much clutch disk you have left through there.