My house is over 300 years old and I was wondering if anyone could offer advice on the best method to plasterboard very uneven brick and flint walls.

Metal dry lining components. Look at the British Gypsum Website for details.

I think you should be able to dot n dab them, see if you can find some adhesive that is certified to bond to flint walls.

Then you can just use a load of adhesive on the dabs and use a 6ft straight edge across the board to check they are level/straight

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