I'm trying to flesh out my first army list (it's a tyranids list) and was confused with the upgrades for different squads. Can you mix and match upgrades in one brood/squad? For example say I have 6 warriors, can I give 3 of them deathspitters, leave 2 of them with the default devourers, and give 1 of them the scything talons upgrades or does the entire squad need to be outfit with the same weapons? Same question for the non-weapon biomorphs. Can 3 of them have adrenal glands, and 3 of them have toxin sacs or must the entire squad be upgraded uniformly?