I'd just cut with some tin snips and trim the edges, if necessary with a
grinder.
The other thing is to do the work with a nibbleer if you don't need 0 scrap
lines cut.
The metal can be worked with a hammer and body dolly (car tool) and get the
dings out and then polish as desired.

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Why isn't there an Ozone Hole at the NORTH Pole?