In article ,
Zymurgy wrote:
Great, thanks for the advice, however after gouging a sample out. the
plaster is only 10mm thick, so there'll be very little covering it
when I plaster over.

Tack it in place with cable clips and simply plaster over the lot.

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*You can't have everything, where would you put it?

Dave Plowman London SW 12
RIP Acorn