Reply To: How to increase stack size?
To termorary modify the stack size, i use savegame editor. Just load your save on the savegame editor, open json editor on tools and there is all you need to termporary modify lots of things. Stack size, inventory slots, tech location on inventory, ship seeds, anything. I say temporary because it does it on your saved game, so if you start a new game, its gone.
Attached pic, hope it helps.