In my research of different paint chip touch up techniques, from Dr. Color Chip to others... I think that this method stands out as providing the best results:

YouTube

But it requires wet sanding the area around the chip with 2000-2500 grit and eventually finishing off with 3000 grit once the clear is leveled down.

How can I make sure I'm not taking too much clear off during the process? Will a paint meter gauge even be useful, because that still doesn't tell you how much clear there is?

Car in question is a 1998 Porsche 911 with original paint.