Look at my shiny rare armor

Space Age. Equip Power Armor MK2 or Mech Armor at Rare quality or better. Quality armour has more equipment grid slots, so it's worth chasing anyway. Produce a Rare (or Epic/Legendary) Power Armor MK2 or Mech Armor - quality modules in its production chain, or upcycling - and wear it. See No room for more for the ultimate version.