My BBQ has no hangars for things like a scraper or tongs.
However, the side-shelf is made of sheet metal that forms a sort of squared-off "C" shape, with two 90 degree bends at the outside edge. This creates a flat flap of metal about 1mm thick and 1cm wide that's folded back under the BBQ.
This thing has two parts: the first part slides onto this overhang and actually has the hooks. The second part locks it in place.
On my BBQ the sides don't get that hot, but they do get warm. I printed this in PETG.
The first version hooks are just at 90 degrees and parts tend to fall off if there's any wind at all. New version "b" uploaded today:
bbq_clamp_on_hook.scad updated, part 2 is the same but
bbq_clamp_on_hook_1b.stl has better shaped hooks and uses a bit less material
bbq_clamp_on_hook_1b_modifier.stl is just the hoops, I used it to print that part at 40% infill and the rest of the part at 20%.