I missed the bit about the down tube shifters.
Yes, just use a 10 cassette and chain with a 10 shifter.
Use your 9 speed cranks, 9 speed front mech and front shifter. All will work fine, pretty sure your 9 rear mech will also work.
@macaroon started
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I missed the bit about the down tube shifters.
Yes, just use a 10 cassette and chain with a 10 shifter.
Use your 9 speed cranks, 9 speed front mech and front shifter. All will work fine, pretty sure your 9 rear mech will also work.