In which case I stand corrected and apologise to the OP.
The headset is indeed Chorus: HS-00CH.
However, the AC-S bottom bracket (111mm) was offered with sub-Chorus groups.
The Chorus bottom brackets were BB-CH213/4 (102mm double) or BB-CH313/4 (111mm triple).
@Scilly.Suffolk started
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In which case I stand corrected and apologise to the OP.
The headset is indeed Chorus: HS-00CH.
However, the AC-S bottom bracket (111mm) was offered with sub-Chorus groups.
The Chorus bottom brackets were BB-CH213/4 (102mm double) or BB-CH313/4 (111mm triple).