Here's an old photo of the cart when I first constructed the top rack. The rack is made of 1-inch box aluminum and will support up to 250 pounds. I was able to sit upon the rack with no problems.



Using a hacksaw, I cut an opening in each end of each section of box aluminum. I then drilled a 1/4-inch hole in each end of the rack and matched it up with a hole I drilled in each handle. A 1/4-inch detent pin is inserted into the holes to hold the rack in place. The detent pins are attached to short lengths of braided stainless steel wire and attached to each end of the rack, just so I don't loose them.



Hope this helps. I'll try to post a video tomorrow if that will provide additional help.

Gary