Outstanding I've been looking for a tutorial to do this for ages. All the others I've found are for loose bearings.
UPDATE: I've just done this, this afternoon and realised I was being a bit of a pussy last time I was trying to knock the bearings out. Bernie's idea of putting the track nuts on the wrong way round so you've got a much bigger surface to hit and spread the force definitely helped. Cranky I'd give up with the rubber mallet and go for a metal one and the track nuts and don't be afraid to give it a good hit - mine were well and truly fused in but a good spray of WD hefty wallop and they popped out no problem