REAR 290mm discs with OEM calipers
Full spec and all parts needed are in my profile thread. If somebody need more pics or info I'm more than happy to give you my help.
And BTW I'm running EBC green pads on rear axle and I'm happy with them. Was using red pads on front, also with no bigger issue, but when I bought new discs they came with pads so I changed all set.
Don't forget to buy ABS sensors if you gonna go for 5 studs.
I do recommend upgrading rear brakes as well as you will lose correct brake balance. Likely you will overheat front ones, but while normal driving all will be fine. /except quicker wear on front