The trail of dribbled oil visible on the 3rd shot was there when I took the wheel off. There was some oil in the bevel box, perhaps even a reasonable amount (IIRC there's not a lot in there anyhow). Where could it be coming from?
Or is the crown wheel bearing Steptoe refers to a different bearing and I'm looking in the wrong place?
Did you not open the filler bolt on the top of the bevel box to look at the level before you levered the seal out??
You're right, there is only a smallish amount in there ...can't remember off the top of my head but I think it's only about a 3rd of a litre (you don't need to know, you just pout it in until its flush with the filler hole when you refill it afterwards)
The oil looks fairly clean in there, and it's hard to tell but I can't see any rivets missing in the ball race cage....check that thoroughly though, and give it a wiggle around to make sure there's no radial movement in the balls relative to each other (ooer missis)
Give it a spin by hand too......there shouldn't be any graunchiness or noise and it should spin nice and freely......I remember doing one with NEil a few years ago and althought he bearing that was in was newish, it span quite tightly in comparison with the new new one, which took a good 5 seconds to stop spinning with a flick of the wrist.
When was it last changed?
If on doubt, stick a new one in anyway
PS and don't lever the seal out like that.....poke a scredriver through it and lever it out from the front face rather than the side edge
While you're there, change the big o ring (8 inch-ish wide rubber band) 'cos for the price of it, it';s not worth pissing about with
should have used a sharp screwdriver through the front of it 
