If the band or individual performers want this done I'm happy to help, but they need to know that genuinely effective protection will likely result is some level of sonic compromise to their IEMs as they hear them. For the level most users seem to want their buds at, protection will need to engage early to provide any meaningful protection.
I might be doing it wrong, but I've always set my brick wall limiters so that they shouldn't kick in under normal conditions. A peak compressor with a ratio of 100:1, with a 0ms attack and a reasonable release, and a threshold set
just above the the highest peak during the loudest part of sound check (and then verified during the show) can still offer some protection without altering the sound the artist hears at all (unless something goes south, obviously). If the gain reduction meter blinks (and something wasn't exploding at the time), then the threshold gets bumped up until it stops.
-Russ