Quick update... I realized after the fact that I had the board upside down in the photos above. I was in a hurry and wasn't paying attention but it does not fit the correct way either. After some more thought, I tried creating my own mounting bracket with some cheap cutting board material and discovered that the bottom of the PCB was hitting the chassis. After some dremel work, it no longer hit the chassis but still doesn't give me enough room to tighten everything down. Someone suggested adding standoffs which I'll add into the mix to try.