I also have the "Special Equipment and Tuning Instructions"Publication #1131,which is 8 double-sided pages w/illustrations for the BN1, but list Le Mans tune-up kit & everything from Aero screen Assembly to Alfin drums to Silencer(Race Type), even diffs & O/D units. It's kinda strange because it was published by "The Austin Motor Company Limited (Longbridge & Birmingham) in association with the Donald Healey Motor Company Limited (The Cape, Warwick). It also goes on to sat that this was the kit fitted to the A-H cars that completed the Le Mans 24 hour race in 1953. IMO I think this was the basis for the later Le Mans cars, could be wrong, hard to say. Wish I had more of the kit though. cheers