You can take that into Ace hardware with you and figure out what size the screwhole is. Then get an Eyebolt or hook or something. They have a good amount of hardware, better than Lowes or HD. If its unbalanced because of the mogul, then use tie wraps, or velcro ties to attach the wire on your shelving to help balance properly.
Another idea I had was that thin metal rope, its really thin. Taking 3 pieces, I would go across one parallel side with two pieces, then the other side with one, join them up at the top, You may need to buy the zinc things to do that, and attach them to the wire rack.
Basically, I think you should just take the thing with you to HD or Lowes, go to the hardware area, then also the area that they have the chain and such. Just sit there for a while thinking about it with all of that hardware in front of you and mentally work it out. Sometime just seeing all your options and try testing it is the best thing todo. I know there are a ton of solutions.