Fulvia S1 clutch

[Alfaman]

Hi Chaps,
I'm in the process of renovating nee rebuilding an S1 Fulvia ('67) which had been used for rallying c. 15yrs ago and then left to idle. The car has a 1.3 S2 engine producing c. 110bhp (1016 cams) but still retains the original 4 spd g'box. Once completed, I hope to have fun in it participating in 'hill climb' events. Having read the correspondence on the forum re upgrading the clutch, I'd be grateful if someone would let me know of the actual Fiat part no for a Vario (or any other make) clutch upgrade, or the specific Vario P/N? The Nos quoted in the forum are not recognizable by the Vario people in England unfortunately. Also, if you have tips on fitting the clutch etc., I'd be most grateful to learn from them.
Many thanks in anticipation, Peter B