Dimensions are fine.
I opened up the PSU and it's a 2-pin molex connector AND it goes into a sleeve so I can only fit a 2-pin in there..... The fan I posted uses a 3-pin and is the only 135MM fan on Newegg.
Ugh.... Is it worth cutting the wire's up? Getting a PSU like mine will cost way over for what I got it for since I got it on sale during the holidays for 2/3 the original price. I really don't want to go backwards on my hardware.
Yes, sure, cut and splice the wires. Make sure that the correct wires are connected (fan to power).
To ensure integrity, 'tin' the ends and then solder them for a good connection. I have done this in order to add fan connections to the PSU power leads. I used electrical tape and also some heatshrink tubing (optional) for a better appearance. (If you plan to use heatshrink tubing, make sure you insert the ends through the tubing before doing the soldering).