Pull the distributor cap and manually spin the engine one way and then the other. If it takes a while for the rotor to move again in the opposite direction the chain is done.
This would be my very first move.
BTW, I push a piece of paper towel into the spark plug hole nice and tight and lightly bump the engine over until the paper pops out, then hand turn a bit more until the TDC mark comes up.
This makes it easily a one person job.