I was just wondering if you could disk cut them off, flush to the face.
Dont know if they are used by the new gearbox for bolting up to, so new threads would be needed.
Depends where the new dowels are fitted to locate the new gearbox.
Can see a lot of hard work and damage, unless they come out easily.
Otherwise a big drill to run through them and see if you can collapse the dowel.
I'm not suggesting any of the above, but just a few thoughts I had reading the first post about swapping dowels.
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