Well I got the rear cluster off. You have to take the access panel
and the rear inside plastic boot liner off to get at all four bolts.
Still a bit of skiffed knuckles involved.
Getting the humidity out of the cluster is another matter.
As said it is meant to be a sealed unit.
Mine looks like an engineering second and you can see where
the supplier heat welded a seam to re-affix the front cover
to the body.
The contruction is a main plastic body that is chromed then a
clear red tinted insert fit's inside this and the clear red tinted
cover goes on the front to seal the whole thing.
Humidity not only gets inside the cover, but also between the body
and the insert.
You need to carefully drill small holes and then blow hot air
at it for hours.
Because of the compartmental construction I needed to drill
x3 2mm holes all on the LHS. One on the back of the body to
the left of the indicator, one on the bottom and one on the LH
edge where the front cover meets the body. And the last one was the only
one I drilled through completely.
The other two I only went through the outer plastic/chrome
and not the clear red tinted insert.
Careful drilling required. If you get swarf going through it's a bugger
to get back out through a 2mm hole.
Anyway the last patch is drying now.
Then seal the holes re-weather proof the cover/body edge
and Bob's your uncle.