yes sir it will help keep them much cooler
Your the man :O
they stay very cold like this. i have a homemade aluminum frame 2 level case with these. 2 cards and the power supply on the top level and 2 cards and the motherboard on the bottom level. the bottom cards are plugged into the 16x ports and the top cards are on extenders plugged into the 1x ports. they have about an inch between them and the temps are about 15 degrees colder than when i had them back to back.
the case is a few inches bigger than the motherboard and is about 13-14" tall. basically a cube with fans on the front blowing through
i got my cables from here
https://cablesaurus.com/you can pay in bitcoins, my order arrived in 3 days and it shipped all the way across the US