I have been wondering that too. Once I've sorted somewhere to live I'll give it further consideration.
Sounds like sensible plan!
It would appear Shimano 9 speed and 10 speed cassettes are the same width, so running friction shifters (as I do) should mean there would be no problem.
@MisterMikkel started
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I have been wondering that too. Once I've sorted somewhere to live I'll give it further consideration.