The most natural sound for an archtop guitar is with our Mandolin Mic clipped to an f-hole, with the mic outside the f-hole. If you mount the mic inside the f-hole, the sound has a mid-range emphasis around 300 Hz and 850 Hz - not good.
The mic outside the f-hole has less gain-before-feedback than the mic inside the f-hole, but the gain might be sufficient. Especially if you have a pickup: send just the pickup's signal to the floor monitors, and send just the mic's signal to the house speakers. Then you can get a loud sound on stage from the pickup, and the audience hears the natural sound of your guitar as captured by the mic.
Here's how: In your mixer's mic channel, turn up the fader and turn down the monitor send. In your mixer's pickup channel, turn down the fader and turn up the monitor send.
The mic's clip will fit in an f-hole that is at least 5/8 inches wide.