Anything that is just clothing is just clothing. Helmets are either "army helmets" or "combat helmets". quite some became "assault gas masks". Armorsuits/sets have armor ratings and weights according to their looks, as good as my eyes could see to horizon. values are a bit flat, just taken base clothing and adding the value of each armor piece.
those sets use the armorslots they show in game and no clothing can be worn underneath. so the sets all have railroad slots and if they include a helmet and/or goggles, helmet and vision slots.
i hopefully added everything more or less accurate with the weights though.
Gunner helmets do not cover long hair, because that way it should be possible to wear balaclavas with most of them. may cause minor clipping issues.

There is only Torsolining for the sets, no limb lining, so a combination of real armor and clothing should still be better overall. Also the Sets are not upgradeable with polymer, fiberglass, shadowed or reinforced - just to keep them more for npc and the looks and not create op armorsets.

the clothing from GOP is !added! to the gunner outfit lists, so "normal horizon gunner gear" is still with the gunners.
changes from "a gunners life" are included, but you need it anyway because both mods do quite some cool stuff.

Optional File set a AP-penalty to horizon backpacks:
-10 for lower Packs and also for upper ones
-20 for lower AND upper ones

Load order:

DT_GunnerOutfitPack.esp
ThatsGunnerLife.esp
--------------------------------------
z_Horizon.esp
z_Horizon_DLC_all.esp (dunno if needed, but some armor looks like marine armor and got the slots, so better with it)
-----------------------------------------------------------------------
(Horizon patch section)
GunnerOutfit_Life_Horizon 1.9-Patch.esp
BackpackPenalty_GOPLife_HZ1.9.esp (optional)

if you use any gunner Horizon west-tek patches, probably load them after this (?)

2.1 just a tiny adjustment to the veterans outfit.
2.2 Contractor Outfit is also armored (partially)
2.3 a tiny adjustment or i just saved the file with a wrong number -.-
2.4 Gunner wear either GOP-gear or Horizon-Gear
2.6 Removes Boni from Gunner Power Armor paint job
2.7 Most Armors should be repairable now (usually combat armor, some minor suits as leather)