Alright, I wasn't quite happy with my VRM temps after doing the Red Mod to my cards, so I sat and stared at the case for a while... that's when my awesome Arc Midi R2 case came to the rescue!
There is a horizontal slot above all the other PCI slots, so I took a slot bracket and super-glued a Silent R2-series 140mm fan to it that is aimed directly down on the VRM heatsinks on each card.
The result:AFTER RED MODDING BOTH GPU'S
2 x Powercolor 7870XT Myst @ 1100/1500 after a Unigine Valley run, ambient temp is 21C:GPU1
: 42C Core, 86C VRMGPU2
: 42C Core, 89C VRMCPU (Swiftech H220)
: 55CAFTER RED MODDING BOTH GPU'S AND ADDING A 140MM FAN
2 x Powercolor 7870XT Myst @ 1100/1500 after a Unigine Valley run, ambient temp is 22C:GPU1
: 43C Core, 75C VRMGPU2
: 43C Core, 77C VRMCPU (Swiftech H220)
So, while I'm still not 100% satisfied with the VRM temps, they're definitely better than they were before!
Looks like this: