I have an open top drum. There's about a 1/4" gap from the edge of the lip to the edge of the lid.
I didn't want to ruin the weber lid because I am planning a UDS/WSM combo build. I got a piece of 72" x 1/8 x 2" flat bar for $4.50. I used three c clamps and worked my way round the top and bent the flat bar.
Just a note, the exact size is 72.25" for the drum's ID. I should have a small gap but my BIL will weld that for me.
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