Well that was erm.... fun....
Firstly, while this case will take a 120mm rad, I can confirm that there is exactly 149.9mm below the centre cable tray and the bottom of the case. This meant that after initial attempts to work out how to fit the rad, there is now a tiny little crease on the top of it. I really hope I don't need a warranty claim now. :-)
Given that I couldn't fit the rad in landscape, it blocks the GPU power cables, then the only way to fit this was in portrait with the fan against the side of the case. That allowed the base to flex a little more. This might be the optimal way, but some choice would have been nice.
Unfortunately the fan screw holes in the Shift do not line up in this direction. They are a fraction of a mm too high on the left (looking into the shift) which results in about 10degree lean on the screws through the fan into the rad, but on the right it is just too much of a stretch to line the rad up. This isn't a big problem given how much this is wedged in, but I really don't want to drop the case now. I've ordered some M3x20mm and when they arrive I can take another look.
At first I thought I was going to be able to mount the AIO on the CPU without removing the MB from the case, but that got rather sticky when the backplate pinged off. If you move it to the MB box, then the box holds the backplate in place, much easier. While I was in there I removed all the stickers from the Motherboard, its just black now :-)