So on my second playthrough of the game I loaded up a bunch of mods that have various effects - 1 more spawning - this caused a swarm of cazadors to completely overrun one of the NCR camps. So, using another mod (buildable bots) I used the bodies of the dead soldiers to create reanimated corpses, dressed and armed with the NCR gear. So now the corpses defend the fort and while they don't have unlimited ammo, they do have more life than a standard recruit. Its a nice touch that they can wear faction armour too.
yet another reason to play the game on the pc.