oh well
but i am still gonna build me a gpu cooling block anyways for under $60.
Got a bench drill gonna buy a copperflatbar $40 and
a pump $15.
Block design

If you decide to do it, do it right the first time. Half ass job only cost you more
Pump is the most crucial part of watercooling.
Also not all pump works the same, i advise to you step back and rethink your idea.