Presumably the punch tool has a limit as to how
far from the edges of a
piece it can reach?
There was a "Q-Max" D type punch, don't know if it is still
available, but
that could be used to pace a hole anywhere in a sheet of metal (it is pulled
through with a bolt, so doesn't need a press of any kind).
That's the type I have. It's not a Q-Max brand, it's RS
(
http://www.rswww.com/ IIRC). I've never seen an odd-shaped genuine Q-Max
cutter (I know they did make sqyare and rectangular ones, though).
-tony