As above, or can you get brackets made up for bigger discs??

 

The size of the disc is governed by the radius in the back face of the caliper, if you fit a larger bracket to space the caliper out you will end up with the pad overhanging the disc and/or the outer edge of the dics touching the caliper.
I used to have 356x32mm discs with 4 pot AP's, but I had to get these the calipers machined by AP Racing in order to do this.
Most of the CP5000 range calipers (the black calipers with dust seals) take a Max disc size of 330mm.

Andrew