The timing marks are on the front of the engine. You need to remove the bulkhead cover to time the engine.
However Mr.Pence has a method of using a vacuum gauge and just turning the distributor.
It does work very well and really eliminates the need to use a timing light.
He has written the procedure in a couple of threads of which I don't remember the topic.
Perhaps if he reads this he can give you the link to the thread.
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