Just fitted a 75mm RSC unit in place of the stock Bitubo on my 2000 sport.   Installation instructions indicate a distance of 39mm between clamp and end of assembly - but I found that this limits movement prior to mechanical stop at full left hand lock (but still ~12 mm remaining at RH lock)   I have adjusted this reference measurement to 47mm (ie +8mm) which now gives ~2mm free at LH lock and ~6mm at RH lock.   Gio