I did this mod about 2 weeks after getting the welder...a dual cylinder rack. It's a $300 dollar option from Miller. I bought a floor model from a local distributor and it came wit a single cyl. rack, so I made my own.
It is also made from that piece of switchgear cover, and I still have some of it left! I think it is 16 ga. mild steel.
If you look closely, you'll notice a gold chain. Yep - it's from an old dining room light fixture. Packrat!
I also used 1/2" one hole straps to keep the gas line for the spoolgun off the floor. I made the spoolgun/MIG torch holder and cable rack as well. Made from scrap 18 ga. (sides), a 4" E.M.T. coupling (the radius the cables lay on), and 1" square tube (the support). Everything mounts to existing hardware of the welder itself.
The "foot" that the cylinders sit on is removeable. It bolts to the single cylinder foot using factory holes. I made it for 80 ft3 cylinders because I was told that is the largest size I can own. Anything larger need to be rented. If I decide to go larger, I would simply have to extend the rear of the foot out. The width is fine.
I rattlecanned this as well.
All materials were free except for a $5 can of paint. I'd say this took 6 hours tops. It was a fun project.