Rob ask on the Flypast forum as well, there are several people that operate them on there,
You will need to register, link here
Historic Aviation - Key Publishing Ltd Aviation Forums
This will give you an idea of the knowledge there and I know they are talking about a 10-1 and 10-2 and you didn't want try XYZ but one post does mention
Gipsy major 10-1 help - Key Publishing Ltd Aviation Forums
"The crankshaft was done by Vintage Engine Tec who did an NDT and corrosion inspection, dimension check and re zulphanise (hope that spellings right!!!!!!)"
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