I don't remember which, but one of the Southeast Asian countries had to do this, but failed to change their bus fleet, so now you sometimes have to exit into traffic.
When renting mopeds in SE Asia, I asked which side of the road they drive on. The man answered "we drive where there is shade". I laughed, rented the moped and returned it 30 minutes and 2 near deaths later.
H stands for 'horeson,' as it seems to have been the most uttered word on that fateful day and in the weeks that followed. It appears drivers weren't quite pleased with the switch to right-side driving!