Factual error: The film's car chase takes place in Thailand, where vehicles are right-hand-drive (RHD) and travel on the left side of the road (as in England and Australia). Yet the American Motors (AMC) cars in the chase (the red Hornet X, gold Matador coupe and several Matador sedan police cars, all 1974-models) are all left-hand-drive cars. Scaramanga's car can be excused as something he specifically imported for himself, but the Hornet is 'borrowed' from a fictitious AMC dealership (none existed outside the USA) and the small amount of AMC vehicles sold outside the USA were shipped disassembled to various companies that reassembled them and sold them under their own company names (AMI in Australia, Karmann in Germany, etc). Companies such as these, in RHD nations, had to modify the cars to RHD themselves in order to be allowed to sell them 'locally'. So the Hornet would have been at a non-AMC dealership, and would have been RHD, as would the fleet of police cars. Naturally, this 'error' was created by AMC's promotional deal with the filmmakers to use AMC cars in order to improve US sales to the US filmgoers.
Factual error: James Bond comes out of the "Bottoms Up" topless bar and down to the waterfront. He jumps on a boat and tells the boatman to take him to "Kowloon side". In fact, Bottoms Up is on the Kowloon side of Hong Kong harbour, so he's already there. If he wanted to cross the harbour, he should have asked for "Hong Kong side".