The Lamby holder should hold it providing the nut isn't seized on. Fit the holder onto a hub stud and fit a nut then give the socket wrench a sharp jab with your palm and it should come undone. To save space when you make a Vespa holding tool from an old rim, drill extra holes to match a Lamby hub.
I tried the Lambretta one but bent it as it didn't fit quite right and the engine rolling about on the bench. It shouldn't be seized as the engine has only done about 80 miles since it was rebuilt last, but it's bloody tight.
I'll make a proper tool when I have time now the urgency has gone. Thanks for the suggestions.
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