don't have a photo but i put them on my xtracycle this way. big difference with my setup tho, the snapdeck is wider than a normal rear rack and it also has a 2" thick foam pad on it. i wrap the pizza box in a beach towel to add cushion and keep the heat in. i then strap it down with some nylon straps. its better to use more straps that aren't so tight than fewer straps that need to be tighter, so i use four 1" wide nylon straps.

its the only way i could figure out to do it, because unlike most cargo haul, the pizza obviously needs to be kept flat, and there really isn't anywhere else on the bike to do that.

i will take a photo next time i do it.