By enchanting a falmer helmet and a circlet with the maximum 29% of fortify alchemy, you can wear a total of 5 pieces of armor that fortify alchemy. This makes your fortify enchanting potions have a total of 37% fortification, and your fortify smithing potions have a total of 147% fortification. So long as you can equip both the falmer helmet and the circlet, this works. Confirmed to work on PC.