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Nope... the other way around is usually fine though.
Check issue number on the Spectrum circuit board (silkscreen "ISS 4B" or something like that), download schematic for that issue ZX Spectrum **broken link removed**, schematic has pinout for the ULA.
Beyond that: official documentation for the ZX Spectrum ULA doesn't exist, but Chris Smith has done extensive reverse engineering for his Harlequin project (even available in book form!).
P.S. check my site if you need to replace the lower 16K RAM
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