That is why I wondered if there was a second marriage as the 1966 one was in Hastings. Or could that be his son?
Someone found 2 marriages with 2 different ladies
I'm not sure that the 1940 marriage is yours as that was a Leslie Race to a Lillian Oldham, they would have had the child you found born there. If you are sure he married Lillian Oldham, I think it is the Coventry one as that was to a Leonard Race. Unless of course he changed his first name again.
I doubt if he would have married two women with the same name. The only way to be really sure would be to get both marriage certificates and perhaps the Hastings one as well.