Help please on the casebacks of Omega Seamaster 300's

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As there were various makers of cases and case backs. I am hoping to get advice from other member on this forum.
Was the tap/angle/thread different from one manufacturer to the other or could a case back by Huguenin Freres fit on a case by Centrale Boites or Piquerez?, and would the modern omega service case backs (166.0324) fit them ?

Any help would be greatly received.

Thank you
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