Say...East Timor in a LHD United Nations Toyota Landcruiser. Took all my concentration as a North-American raised LHD guy. The urge to be on the other side of the road is powerful, especially on gravel roads/unmarked 3rd world highways, etc. I don't have any issues driving RHD cars in NZ or Australia. I'm currently working in Papua New Guinea which is RHD. I occasionally walk all the way around the vehicle before I get in, 'cause I forgot which side the wheel was on.