If you want to keep the 4 bolt pattern (as most do), then you will need to redrill the discs
For the front brakes, you can upgrade these fairly easily to R32, R33, S14, S15, GTR
You will need to:
remove old disks and calipers
redrill the disks
remove or trim the disc backing plates
fit the new disks (fit straight on)
fit calipers (bolt straight on)
grind a couple of mm off the original banjo bolts
fit lines
all done