A punch head comprises a low profile hydraulic anvil piston with a punch across from a die on opposite sides of a gap between two legs. One of the legs comprises a position sensor disposed on the bottom of the leg. For example, a plurality of punch heads are disposed on a jig or frame and are positioned using one or more of the position sensors. For example, the position sensor is a mini fiber optic position sensor mounted in a recessed portion at the bottom of one or more of the punch heads.