The short answer is that those codes were relevant in 1969 when the engine was being built, but are not relevant now after many miles and years.
You need to use green plastigauge and figure out what bearings will give you the proper clearances. The place to start is usually green if you are unsure of what you have now.
You MUST get a shop manual. NOT an aftermarket manual. Only the original Honda manual (green cover) will do!
Good luck!
