You don't really need to create an addon to do this. Just create a resistance officer and a blackop. And then group them together so that the resistance officer is the leader. Then put this in the officers init field:
deletevehicle this
this will make the blackop join the resistance side. Then you can use the addweapon/addmagazine command to change his weapons.
Or... an even simpler way would be to make resistance friendly to west