Greater than the sum of its parts challenge - blps challenge farm method

I used this route because it allows you to farm the lowest level weapons in the game, which is very helpful because when youre farming for luneshine weapons, the lower level the weapons are that you put in the grinder, the less moonstones it costs. Which if you look when i go to grind it only costs 2-3 stones. You cant get luneshine shields or equipment, only weapons. Only grind white, green and blue for low costs, when you grind purple it costs around 8 stones. You can also regrind your luneshine weapons at the same cost so thats clutch. The only reason i farm og godzilla at the end is to get my moonstones back. Also if youre wondering why im barrel stuffing enemies, its because in trying to max out my point blank kills challenge so that the undiscovered shotgun challenge will unlock. Not sure which is worse for the challenge accepted trophies, grinder challenges or robo jenkins. https://store.playstation.com/#!/tid=CUSA02893_00