If you use this terminal mount fuse block-
https://www.amazon.com/Blue-Sea-Syst...gateway&sr=8-7 you mount it to your battery + terminal and then run two 10 gauge plus from each controller to the block and two 10 gauge minus to the - terminal or a nearby negative buss bar.
With a four battery house bank just hook it up to the + and - terminals unless it is series/paralleled wired GC batteries then make sure you wire it to the +/- 12V terminals.
Use this 60A fuse-
https://www.amazon.com/dp/B001B04Z5Y...ing=UTF8&psc=1
David