It's a built up bike so I'll strip it down and weigh it
Do pictures first or compare the stay canti cable stop to a Prestige
Just to add now I'm on the computer, not a phone.
My belief is the Prestige used the wishbone cable stop as in the pictures above always for this year.
The Clockwork used a two pronged side to side type thing at this time. (it may have used the prestige style at some point earlier on* ?)
Of course if it has one the style above it doesn't mean it is, but if it doesn't I think it means it isn't
As an example (For reference A303xxx serial, top pull with roller, not the flat bottom to the reinforced seat tube section for this later 'future/zero's/square/.. style graphic)
Clockwork similar era
* the offset stay lower then the top tube, '92-ish ? bottom tube routed ?