If that is the original engine, it has the wrong timing cover. Timing mark should be on passenger side, water inlet on left. Timing would be way off. If it is a 71 could be either.
I have never seen a timing marks on the passenger side of any 70 or newer small blocks, they have always been on the drivers side.
But with Mopars stranger things have happened.
My first week build 73 Duster had seats in them from 72, production line must have been using up inventory.