Dual 1080 with 1440p? The 1080 by itself will preform fine at 1440p without a second card to back it up. A 1060 will run most games at 1440p at max settings, so I don't see why the top of the line wouldn't.
I'd drop the second 1080, keep the current parts that you have--except for the 240mm radiator. It's not going to fit in that case. Either switch the case or go for an air cooler. A good one, like the Noctua NH-D14, will keep that temp just fine for you, even when overclocking. Use the extra cash for a good mouse, keyboard, headset, anything else you need.
Getting a non-reference card is going to bring the temps down and the performance up.