Mikepier wrote:
....
I don't think you can make the seam in the middle. If you did then you
need a support for the 12" overhang. ...

I don't know that that is _necessarily_ so. OP doesn't say how wide the
overall piece is, only that he has only a 9" overhang.

There are several options for fastening the piece down other than its
own weight...

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