What I did was set one of the guys in the UAZ to Resistance and a high rank, then linked the other East guys to him and the UAZ. (Sorry if I don't explain in your terms, but I've only been at this a week or so).
I still have a lot of problems understanding how triggers and scripts go together. I know a trigger can fire a script, but the complexities are still foggy to me. As with anyone, it'll all become suddenly clear one day soon. For now though, what I'm after, in the simplest way (hah!) is:
a) When I shoot someone, East or Resistance, I want others within hearing distance around them (ie., ricochets, screams, etc) to go "Holy f**k!" and start shooting back.
b) Make everyone do the above, regardless of whether they're East or Resistance (since in my mission, they're working together).
I think I'll take another (long, long...) look at the enhanced AI script I mentioned, but when I tried it earlier today it said that AddEventHandler was an error. Is that not available in 1.46, or did my hacking around destroy the script do you think?