Remove all the screws (13 x M6 - 13.5Nm) holding on the alternator cover. The screws are shown here and, to aid reassembly, the lengths are:
A = M6 x 20mm (x 2)
B = M6 x 25mm (x 7)
C = M6 x 30mm (x 2)
D = M6 x 30mm (special screws x 2)
Remove the inspection cover (2 x M6 - 5Nm) being careful not to lose or damage the o-ring.
Attach the puller using the two vacant inspection cover screw holes and nip it up. Then tighten down the centre screw against the end of the crankshaft until the bond between the covers is broken. Pull the outer cover away and, if you're not unplugging and removing it completely, use a bungee or similar to suspend it from the handlebars so as not to stress the cabling.
Use a scraper and/or silicone gasket dissolver to completely remove all traces of the existing sealant. I used Threebond's own 3911D, which really speeds up a tedious job. It's designed to be sprayed on but I used a brush as I didn't want to risk it damaging the paint. Cover the inside of the cases to prevent bits of old gasket from dropping inside and possibly finding their way into the oilways.
Reassembly, as they say, is the reverse of removal. Completely degrease the mating surfaces and then apply a continuous, even bead of Threebond 1215 on the cover only, being particularly careful around the screw holes and dowels.
It may not strictly be necessary, but the manual says to replace the gearchange shaft oil seal (937831524) and at only around £3, it would be a false economy not to. The seal should be replaced after the casing has been bolted back on and after damping with alcohol.
I also replaced the two o-rings (88641731A) on the clutch pushrod as they're less than a quid a pair.
Hope that's helpful to someone.