So I'm late on this one.
I love that combination, and have used it a lot:
Create 3 presets for Mic In. Set one at 0db, another at -12db and at the 3rd at -24db.
HOPEFULLY you can pull the show at -12 and start with that, but if you want to change the pad you will have to stop the recording and change to a different preset and start again. You can do that in less than 20 seconds, then adjust the input level, but that's the only way to do it.
You get 24db of volume you can cut with the input buttons on the side, but they are just that: start with them all the way up to 0 and lower the input to -24, -23, etc until they get you down to mute. So if you can start with the -12 pad and only have to lower the input to -12, you have wiggle room. Make sense?
I always hope for an opening band to sort that out.
Hope it worked out!