Cowl mounted gauges

Had a quick search, but no solid answers...
Im hoping to cowl mount oil, temp and fuel pressure, two questions...how have you mounted them with trashing the cowl bars? Im thinking of drilling and tapping a plate, dropping it in the hole and securing the gauges to that..
Secondly, has anyone notched a small section on the rear lip of the hood for the lines to go through? Will check with some plasticine if theres enough room without cutting first, which is the preferred scenario...Ill use secure the lines together under the bonnet near where they come through
Seen a few pics here but all the threads are 5+ years old...