Where'd you get the wheels?
I'm using a vintage Craftsman roll-away for a welding cart. I don't have a bottle rack on it yet, nor have I done any of the other modifications I want to do (hose holders, power strip, fire extinguisher, etc).
I like using a roll away, because it makes storing all the tools and accessories really easy... extra tips, tip pliers, magnets, copper backers, wrench for the bottle valve, tape measuregloves, leathers, extension cord for the welder... helmets go in the bottom storage cabinet. Not only does this keep it all in one place, but being in drawers keeps the dust at bay... nothing more annoying than getting shop dust all over the helmet.
-Brad