As an interim solution, I would split your rigs in 2 clusters and make sure you run one cluster from a different fuse.
I'm planning on taking over the spare guest room (different fuse).
I've already taken over the office. Muhahahaha !
My wife complains that "It's a different microclimate" in there.
Duh ! There's 4 graphics cards hashing !

I have 8 cards hashing atm with a cheapie window ac unit keeping it all relatively cool in my bedroom. One side of my room is 10+ degrees hotter than the other side. Its rly weird to move 2 feet and feel the temp change. Laying in bed its about 75f, sitting at my computer by the rigs its atleast 85f. lol
Get an electrician.
+1 Assuming you even figured out which one to purchase, watching you try to remove the old one would probably give me a heart attack.
I've changed breakers b4, I was just looking for something better than the ace/homedepot $10 special. You don't have to know a hell of a lot to change a breaker.