Here's the place i got my SEM from:
http://www.nwsr.co.uk/
Type Landau into the search box and you'll see the different options that come up. Found them useful to speak to as well, they do a whole range of repair materials etc. I would recommend getting a plastic adhesion promotor as mine has chipped on a couple of edges. I think it was just bad prep, as they rest of the panels are very tough... tried getting it off with my finger nail and it wouldn't even scratch.
I like the idea of celly though. If it melts into the plastic then it sure as hell won't be coming off, as it's acting almost as a dye at that point
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