it shouldn't be too difficult. just make sure you have the plumbing to run it. I have a hob
that came with holes already cut so you should be able to buy one preset. I would recommend checking home depot or a lfs
for a bulk head and a hose to run it if you plan on a diy
. then make sure your fittings are snug and it should work fine.
I have two over flows in my tank. One goes to the sump and the other to my fuge. The fuge has an overflow that feeds to my sump which pumps back to the main tank and to my protein skimmer which feeds back to the fuge. using the overflow makes my small fuge and smaller sump act like one big tank.