Just to clarify....... I do in fact know you do not need to loosen the lock nut on the headset to remove the stem. Perhaps my grammar could have been better but I simply suggesting the OP use a 32mm wrench as a "GO"/"NO GO" gauge for determining stem diameter.
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“One morning you wake up, the girl is gone, the bikes are gone, all that's left behind is a pair of old tires and a tube of tubular glue, all squeezed out"
Sugar "Kane" Kowalczyk