First, and most important, don't use the template unless you have placed it over the heater core to ensure the holes for the tubes are positioned correctly. Historically the template has to be redone for those holes. In terms of placement, if your template, when tested on the heater core, lines up with the bottom of the plastic housing, then place it on the firewall to allow a little clearance above the 2x2 tube. So, for your photo, let's say the template lines up with the bottom of the plastic housing, then put the template 2 1/4 up from the engine side of the 2x2 tube to give you 1/4" of clearance. Measure from the bottom of the 2x2 tube, not the sheet metal.

All of the above applies to the Roadster. Not sure which vehicle you are referring to. Consider adding those details in your profile and they will show up at the bottom of each post that you do.

Pat