> I'm told that IPA will get through the worst of it - but I 
> don't have any,
> and when I asked in a chemist (where you used to be able to 
> buy stuff like
> that), I was met by a very blank stare.
Must read all posts on a subject before replying... <G>
I buy IPA from a fibreglass supply place - 
http://www.cfsnet.co.uk ; I use it a fair amount for things like degreasing leather prior to dyeing it.
Or RS sell it.  But you'll pay more for it through that route - about 3 times more, IIRC.
Peter