[deuce_roadster]

If it were me, I'd clamp an exhaust manifold on the piece of steel I was going to use and using transfer punches mark the holes and them take them to the drill press. Why go to all the trouble of making a template, then transferring those marks to your steel? You have a couple of chances of having something move and be off.

Or if you really wanted to make it complex, create a DXF file and take that to a CNC mill or a laser cutter!