I would not suggest it, they will fit in your mobo they need about 2.5 slots. The problem starts with the rest of your setup and case. I had a corsair 500r case and tried 2 290's with g10's and h55 coolers while also having a h100i on my cpu. You have a limited reach with the clc's, and finding places in reach to mount the 2 120mm rads wasn't a problem but keeping good cool airflow in my case was. I ended up putting them in separate rigs.
I don't know what case you have, maybe you can make it work , but with a full tower with losts of room I would think you would run into problems with the tubes not reaching where you want them to.
If you want to water cool your gpu's I would suggest running a custom loop, I would oc your cards and see if they get hot enough to justify it first, just make sure you have good airflow in your case.