Try to find the recommended spec for the crankset, or whatever was used before. I'm not great with old standards but here's a Sheldon chart. https://www.sheldonbrown.com/bbsize.html
Thanks very much, should have known Sheldon... Much appreciated
@jambon started
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Try to find the recommended spec for the crankset, or whatever was used before. I'm not great with old standards but here's a Sheldon chart.
https://www.sheldonbrown.com/bbsize.html