OK here is my method – now this was particularly rough and ready, learning as I went along 😯
So, pull out the split pin from the nut.
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Now this nut I tried vigorously to undo but with the gearbox on the bench it was hard to hold everything in place and get a decent torque on it. So I manufactured the tool that is detailed in Drawing #27 of the workshop manual which helped.
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and I also applied heat to nut.
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