My apologies (again) for the lack of updates, been snowed under with work!
BUT
Now re-thinking mounting the 1080 to the side of it, Phobya make a case specifically for mounting the 1080 (Called Ultrabig Watercase V1 or something or other), I would usually just go and buy the case, but as it is I have 2 cases sat doing nothing (NZXT Gamma & Corsair 500R) and don't need an 800D taking up room collecting dust either.
So I'm going to get drilling some holes, hopefully starting this weekend if I remember to take some set-squares from work and leave the 1080 passive. My change of heart on the matter is that a replacement panel is only $20, so if I wreck it, its not going to dent my wallet buying a new panel.
Doing this I'm debating leaving out the RX120, purely to give me room for routing the tubing, so all in all going to end up with a 360 + 1080.