Dell Optiplex 960 SFF PSU Upgrade

Hey all. So I recently purchased a Dell Optiplex 960 SFF used cheap and am looking to upgrade the PSU. From a few other threads here some were saying it's a TFX unit. after looking at it the dimensions seemed to fit so I ordered this: http://www.newegg.com/Product/Product.aspx?Item=N82E168...

While it almost fit it wasn't quite right. The fan sticks out just a hair and hits the motherboard. The second issue is since it has to be turned so the fan faces in towards the center of the case then the screw holes don't line up correctly.

Does anyone know a PSU that is 300W or about that will actually fit correctly in the 960 SFF. Also now that I think about it what form of motherboard does the SFF use. Is it a Dell proprietary style?

Thanks.