So I set the PCI slot to Gen 2 and got it to show up a few times both in UEFI and in the Device Manager. From there, Claymore refused to even acknowledge that I had any GPU's installed. I did a complete wipe of installed drivers and reinstalled them all. That did take care of the Claymore issue.
Here's where it gets weird. During the restarts for the drivers, I noticed that sometimes all 6 GPU's weren't getting recognized. After everything was installed, I decided to investigate. I booted to the UEFI ten times in a row, each time checking to see which PCI slots were registering. 4 times all 6 appeared. 2 times both PCI 6 and PCI 4 didn't register. 4 times only PCI 6 didn't register. I then switched the PCI 6 to Gen 1 and haven't had a problem since (granted, I've only restarted 4 times and called it good for the evening as I'm tired and frustrated. Figure all 6 are running stable, temps are low, smoke detector tested hanging above it...good enough for tonight haha)
The only thing I can come up with is that I don't think the mobo is getting enough power for all of the PCI slots. There were times when I was booting it up that it seemed to hang before even the UEFI screen came up. I don't think it's due to the PSUs so much as it is the board itself doesn't have the solid capability to run 6 GPUs.