When I gutted my 40 and flipped burner, I re-mounted the element cover for protection.
I like the infrared treatment here. For the IR radiated downward, the shiny foil is reflective and that thermal energy is significantly reflected back to the cooker region. You DON'T want the red-hot element radiating downward to a dark rusty bottom where half its considerable IR heat gets air-convected away to the outside world. The only thing I'd suggest different here is to wrinkle up the Al foil before laying it down so instead of laying
flat on the bottom, it only touches on the lines where a wrinkle touches. That reduces the heat that is
conducted to the lower floor of the smoker. I agree catching drips and aiding cleanup is important too.
The upper foil functions as both IR shield and re-radiator. You DON'T want the element to be uncovered otherwise food on lower racks get an uneven radiation pattern. If you have doubts about this, place a piece of white paper on the lower rack without the cover. As you raise the temp, you'll see a brown pattern develop on the paper in the shape of the "shadow" of the element shape. (Remove it before it actually ignites.)
For this shield you prefer a relatively thick piece of metal, preferably dark in color underneath, to intercept the IR and conduct the heat throughout its thickness. Since it will not likely glow red, its heat will mostly be convectively carried away into the smoker. What little radiant heat is left will be reflected UP (but uniformly) due to the shiny foil cover on its surface. And again, it's good for cleanup.
Most materials get softer at red-hot temps so although the element appears to hold its own weight just fine supported only at the connector end, I don't recommend it. I suggest you form two "feet" of thin sheet steel notched in a V or half-circle on the top edge for the element to rest into. (You'll note most kitchen ovens implement supports like this for their elements.)
