you didnt hear it from me.
go to Vulcan steel in Dunedin, and ask what damaged sheets they have of 1.6mm or so, they sell it cheaply, often they have only a slight bend of kink on a corner which you can cut around, or bash flat with a hammer. steel deck in an enclosed trailer might have some benefits too.
Ive had sheets for $50 or so from them.
but shhh its a secret!
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