Just wanted to update this after a week of using the G12/H90 combo for anyone still on the fence about going through with this mod, mostly to share the things I like about the way I did things and what I would do differently.
First and foremost I wish I had went with an AIO with longer tubing so that I could have used a top/rear exhausting push/pull radiator mounting rather than the current front intake pull/(kind of push?) setup I was forced to use. I definitely underestimated how much the Cryorig R1 I am using would effect radiator placement, which did in fact have a decent amount of room for a radiator and fan above and behind it, but collided with the hoses coming out of the radiator in both top and rear exhaust setups which was something I hadn't considered. Because of the tubes still being somewhat inflexible, even a front mounting put more strain on the card than I was comfortable with so I used some radiator mounts I had on hand as spacers which you can kind of see below.
Next, I wish I would have taken the money I spent on heatsinks and thermal pads (~$30?) to instead buy a Noctua PWM fan to replace the 3 pin fan on the G12, along with some thermal probes compatible with my Mobo to place on the VRM/VRAM so that I could use Ai suite to control the G12's fan and set an alert in case they reached temps over 120C. It seems that the VRM/VRAM will do fine without the stock midplate (In my specific setup at least) as long as you have decent airflow in your case and the ambient temperature in your room isn't 50C. Also, if you decide to go without heatsinks you have the added benefit of not having to worry about causing a short circuit or of them falling off since they will be hanging upside down. The Arctic pads I used have held up well so far, but it has only been a week, so time will tell if they fall off or not.
All in all though I am very happy with my choice of water cooling my 1080 Ti FE, which performs much better with the lower temps thanks to how GPU boost works, and has the advantage of being able to use the G12/H90 on my next card as well which was a big selling point for me.
Attached Image(s)