How to mount fans on top of H100i for exhaust

Hello there. I just bought a new rig and have been setting it up this afternoon when I ran into a slight problem. I bought a 750d with a h100i corsair cooling system which both are great but I the snag I hit was when I attempted to mount the fans on top of the radiator in a pull formation so as to exhaust through the top of the computer. For the life of me, I can not figure out the easiest way to screw in the fans and radiator attached to the top of the case. Its very awkward to screw in the fan to the radiator while balancing it and would like to know if I am just dumb and have been doing it the wrong way.. Any tips on how to properly align and secure fans on top of the radiator so they can pull air from inside the case through the rad and then out the top?



Thanks!