As said, totally depends how you install it.
Is your fan(s) to go in front of the I/C or behind?
I installed a GRS with kenlowe inbetween and had to take some off the bumper, but mainly the skinny uppermost bar. I also made some little custom spotlight brackets so i could still have them fitted.
Best to fit eveything as you want it and then your last job should be to mod the bumper to suit.