[75 911s]

I've done about 5 or 6 valve adjustments as well. I made my own gauge, and then bought the kirk tool, which I have used twice now. It feels way more accurate in the phase of tightening down since you can see gap movement as you tighten. When using a feeler gauge you have to eyeball it and that's not so easy on the valves tucked back in the engine bay. If you're doing it with an engine drop, it's a push between a feeler and the kirk tool. I'd probably use both still.