Glue on the third block to form the carving blank for the knuckles.

 

To the underside of the hand-rest blank glue on a third block of wood. This piece is 1-1/8 inches thick and 1-3/4 inches long. I leave it's width over-size and trim the waste off after the block dries. I take time to plane and sand the underside of the two piece top assembly to get a good glue joint when the bottom block is glued on.