I might just zip tie it. I'm running the HP 1200w on 120v and it powers 4 of my 6 GPUs, it gets warm to the touch. I think if I ran it on 240 it would run cooler, I'm looking into that as a project for this summer.
Those parallel miner rigs are super clean.
Thats exactly why ive built two similar. I use a decent heatsink and some thermal pads zip tied to the psu to help with the heat and stop the fan spinning up too often.