respecting your elders

It was polite of you to tolerate the old man's story. Correcting him would have done no good, as he would have probably been offended while still thinking that he was right.
I have a hard time keeping a straight face and a shut mouth when dealing with these people. Guys with no classic car at all, calling every 340 or 440 a six pack, bragging about their POSI axle, etc.