I had to make a few modifications to my 500R to fit the H110 radiator in the top. First of all, the tubes will not clear either front or back so I decided to cut some slots at the front so I could still use the rear fan. Next the cover would not clear the radiator so I shaved down the ridges on either side of the plastic frame. The last modification was to drill out the mounting holes to screw the fans from the bottom into the radiator. There is not enough clearance to use grommets on the mounting holes.
The H110 would fit in the 500R with the radiator inside the case with the hoses to the front, but the mounting holes are threaded. The holes would still need to be drilled out to mount the fans on top with the screws through the fans and into the radiator.
It seems like unmodified, the 500R will accept a 120 mm x 240 mm radiator or 140 mm fans.