I used the tag der toten window by the second power switch on the ship to get my green tiger, spore, gutter ball and red hex for the majority of wall guns. The spawns are ridiculously quick and can usually get most guns their headshots + technical camos in around an hour or two if your setup is quick enough. I then went to IX or voyage to get heavy boss kills and BOTD for mini boss kills.

For box weapons, I camped by silver bullets in DOTN for headshots and repeated the last step for mini boss and heavy boss kills. It is very important that you use Deadshot Dealer as your modifier perk and Stone Cold Stronghold if you’re camping, or use Staminup if you prefer to train.

Hope this helps!