I'm not going to do the work unless I'm getting paid to, but I've done plan review for a similar project here in CA and it was pretty easy to show that the fire rating was required. It was not easy to build, in fact I don't think they have yet come up with a solution, if/when they come up with a way I'll post it. Ideas discussed were temporary wall, demo and rebuild or removing sections of one or two studs at a time and replacing with CMU wall. BO said whatever you decide to do, provide a stamped plan.