I'm changing out the differential in my GS-R and it is entirely too easy. You've got to pull the axles, and drop the transmission. Then its a bunch of bolts, a snap ring, and a couple of shafts on the shifter assembly. After thats done, you take the gears out (they lift right out) and lift the differential out. You then transfer over the ring gear. Put the new one in, and here's where it gets tricky. You have to use a special tool to check the tension on your lsd. If its not within a certain limit, you have to get a new 79.5mm from honda, that will bring that torque into spec. You definitely need a helms manual. Then its just a matter of sliding everything back together. Be prepared to change your axle seals out though. Mine had some seepage and had to be special ordered through the dealer. Its only 20 bucks, so you might as well do it while its handy. Its better than ripping everything apart and waiting two weeks. You'll also want to replace a couple of crush washers in there.

Oh yeah... here's some pictures: LSD pics