Thanks for your response, I'll definitely measure everything out. BTW, which perspective is the LWD measured? From the back of the computer or from the side?
As for why I'm considering this upgrade, I'm being offered a ridiculously low price from my friend who won one for free. I'd like to eventually add on things like a better video card (only running a 5770HD atm), SSDs, and in the long run make a new system where I could just transfer over some of the parts (like this PSU) into the new one.