Conversation so far:
How did The Sweet initially get started?
Guitarist Mick Stewart joined in 1969.
Stewart had some rock pedigree, having previously worked with The (Ealing) Redcaps.
who else is in the group?
In late 1965, that band became The Phil Wainman Set when the future Sweet producer joined on drums and the group cut some singles with Errol Dixon.

Question: Were there any other members?
Self-contained rewrite: Aside from guitarist Mick Stewart and Errol Dixon, were there any other members of The Sweet?