I am not sure but I believe it possibly was to give more room around the carburetors etc on the R/H side of the engine,one of the problems I had when I ran it in its original body shell form ,was getting enough room for a decent exhaust system on the L/h side of the engne compartment to suit the Lotus Twin Cam engine.I never really noticed the fact that it was L/H drive when I raced it ,it might have been better at Bay Park for seeing the apexes etc ,hard to say as I always went good there anyway