Simple S&D
Caches spawn automatically inside the (static) AO, have rearm on them and vehicle maintenance pad, can be destroyed by interacting with them (long hold action). Can build statics around it.
INS spawn on MB and around the cache (can be blocked like FO), can't build FOs, can't rearm on RPs, have no maintenance pad in MB.
Everything else is the same as default.
The idea is that Blu will be able to find the cache just by noticing INS activity because INS will be spawning on the cache, rearming on it and getting supplies and ammo for statics from it. No artificial intel system is needed.