Does anyone know what's the deal with the various armor pieces and how they work on the character models? I picked up Curie as a companion ('cuz why not). She's essentially unkillable since I'm not playing on Survival difficulty, but I figured that a modded set of Combat Armor would give her a bit more staying power. So into her inventory we go; equip that, that, and that; use this weapon rather than that one; here's some ammo to keep you going; and voila! A cross between Victoria's Secret and Guns & Ammo was not quite what I had in mind. A bit of experimentation finally got her into some fatigues with the armor on top, but I'm not finding much consistency in whether the underlying outfit stays in place. Tried it with one of the settlers that I assigned to guard duty and hit the same problem. I can have clothes or I can have armor, but apparently not both. Obviously I'm missing something here, so I'm hoping that someone can lend a clue to the clueless. How do you get both clothes and armor?

http://fallout.wikia.com/wiki/Fallout_4_armor_and_clothing

Some gear is clothing and others are outfits.

Clothing works as "underlays" while not all outfits work with armor.