Hello fellow 68k users! 
I tried the same thing with a Quadra 700 case and PSU some time ago and it worked without problems. Didn't had to cut any holes in it, too, because the ports fit in perfectly. I was just limited to two nubus ports, because i didn't wanted to harm the case
.
However, the strange thing about it was, that it really detected a Q650 mobo although it was a Q800 one. I don't know why that happened, my only guess is the different PSU.
I tried the same thing with a Quadra 700 case and PSU some time ago and it worked without problems. Didn't had to cut any holes in it, too, because the ports fit in perfectly. I was just limited to two nubus ports, because i didn't wanted to harm the case
.However, the strange thing about it was, that it really detected a Q650 mobo although it was a Q800 one. I don't know why that happened, my only guess is the different PSU.