CM Stacker 810 PSU Help

I just bought a CM Stacker 810 case and a Seasonic S12 600Watt PSU. The specs for the case call for an EPS 12V power supply which lead to me the S12. For this case the power supply installs in the bottom via a bracket that screws onto the case from the outside and then several screws go through the bracket and into the power supply. The problem is the screw holes on the power supply do not line up with the screw holes on the bracket. I can think of two options to get around this. Send the power supply back and try to locate one compatible with the case. The second option, which makes me cringe to even suggest it, is to drill new holes into the bracket so they will match up with the power supply. The voices in my head are telling me, and laughing, option 2 is playing with fire but if there's a chance it could work I'm willing to try as everything else in the power supply is compatible with my set up. If locating a new power supply is the only option does anyone know of what one is compatible with this case? Sorry for the long winded post. I'm not very good at explaining things.

Mhome