If you have a hitch and no receiver shackle:

Put the loop inside the receiver and insert the dowel through the loop and put the cotter pin into the dowel. A cheap alternative to a D-shackle.

If you don't have a hitch:

You could put a D-ring through your shackles in the back. I would rather use the front tow hooks on the vehicle being recovered and the receiver shackle on the vehicle doing the recovering.