Hey Trig & Welcome, Might try that orientation out,Nice, not sure I'd route the AIO pipes that way though.
Can you rotate the CPU block 180 degrees and run the pipes from the left of the CPU and then down and put the inlet/outlet on the rad at the bottom to enable you to get the top of the rad a touch higher than the CPU block so the air gathers there?
Yes, I have to see, may try that way when white fan arrives.I managed to route mine out of the way of the nvme heatsink on my board and down under the PCI-Ex slot, obviously, you have gone a bit further off fo the reservation with your build than I did so it looks like you have oooodles of space under the slot to run the pipes which would probably mean you could drop the rad a bit and still have the rad caps higher than the CPU block.