pre pierce drill

Hi I am using sheetcam for a water jet cutter , when cutting laminates I need to drill a pierce hole before cutting otherwise the high water pressure separates the laminates. I am installing a pneumatic drill head 100 mm from the cutting head on the x axis .
what i would like is the gantry to move X -100mm , pneumatic drill drills a pierce hole , gantry moves back to 0 (x +100mm) and the cutter starts cutting from the drilled pierce hole , any suggestions
there was a post on the forum but its been deleted Mach3 THC prepierce.scpost if any one has it so I can look to modify
Peter