HERBIE ON HOB OVERFLOW

[CM125]

So Ive been recently converted our large tank to a Herbie setup and it has done awesome! If anyone is thinking about I highly recommend it. We only had 1 overflow so the return had to come over the back, but its totally worth it. Anyways Ive decided I want to do this on our little tank as well. This tank runs a HOB overflow. In principle this should still work. I will be drilling into the side of the back box for my emergency, as high up as possible. I will also be rigging up a float valve to turn the pump off if things go sideways. I couldn't find any others who have done this so im guessing Im just looking for confirmation before I drill into my overflow. Based on my understanding of everything I think im good to go, but if anyone has anything to add or think about please let me know.