Maybe it would be easier to just open a window in your room! Sure, putting new fans on it would cool it down a bit, but as the CPU temps are fine I wouldn't be going out of my way to cut holes in my case. When it gets really hot in mid summer I do tend to take the side casing off to help cool things down a little.
It's the room temp you need to bring down a bit as my system temp never gets above 40c and is usually around the 30c mark.
Do you live in the middle of a desert??? lol!