Inverted fork seals, with pictures!
 

Everything's in bits awaiting the new seals, no big surprises and no special tool required. Before you remove the forks from the bike slacken the top cap and the bolt at the bottom several turns. With the fork leg off the bike unscrew the top cap, there's no spring pressure to worry about. This is what we see:
http://pic100.picturetrail.com/VOL11.../397322617.jpg
We now have to remove the top cap from the damper rod, use a slim 17mm spanner on the flats below the rubber washer.
It's not necessary for changing the seals, but if you want to dismantle the spring and damper rod this collet has to come out. There's not much spring pressure and I managed with my bare hands. The lower end of the damper is screwed to the plug at the bottom of the sliding leg, unscrew the plug (it has flats on) and the damper assembly comes out.
http://pic100.picturetrail.com/VOL11.../397322620.jpg
Now our attention turns to the other end, the axle mounting has to come off, this is where I was expecting trouble, after removing the bolt we slackened earlier I waded straight in with a blow torch. After a couple of minutes and a bar through the axle hole I could work it off. After cleaning all the corrosion off it now fits back on with firm hand pressure. If you lived somewhere warm and the bike's not been out in the winter weather you should get away without the heat.
http://pic100.picturetrail.com/VOL11.../397322619.jpg
Depending on the size of the screwed in bottom plug you may now be able to pull the sliding leg out of the top. Mine didn't, with the axle mounting off, the leg slides up far enough to expose this split bush, carefully prise it apart and remove. The leg will now come out of the bottom.
http://pic100.picturetrail.com/VOL11.../397322616.jpg
With the seal housing exposed remove the wire clip and prise the old seals out.
http://pic100.picturetrail.com/VOL11.../397322615.jpg
This seal housing's a bit odd, with the seals out it's possible to knock it up the fork leg, it's retained by a wire clip and the fork seals. I'm 99% sure that you can't fit the seals in the housing and then fit the housing to the fork leg.
http://pic100.picturetrail.com/VOL11.../397322618.jpg
The seals are a common size, 41x54x11mm, the same size as CBR 600's and Ducati Monsters.

Jonathan.

Excellent post! I'm going to add this to the DS stickies.

Thanks for taking the time to document your work with photographs. :)

Spud :)

Very nice, thanks for the photos and description.

Thank you! I've never worked on USD forks before.