Mounting a cabinet-type smoker box to a UDS

Last summer, I bought an insulated stainless steel food pan holding cabinet. My Plan is to mount it on top of my stainless steel UDS by cutting out an opening in the top and bottom. I'll be using perforated stainless steel full-size steam table trays instead of grill grates because that's what the thing was designed to hold and because they are much cheaper than buying grill grates.

I could use a little stainless welding/fabrication help. I can furnish the MIG welder and beer (after the job is done).

Mark