I agree. I've come across many instances where names are spelled differently in vital records within the same time period. For instance, Queirós sometimes spelled Queiroz, sometime Queirós. In a current family from the early 1700's I'm working on, Corrales, I've seen it spelled Currales, Corales, Corrales, Curralles, etc in different records within the same time period. I suppose it was what the priest felt how it should be spelled LOL. I feel that for consistency and to avoid duplicates it's probably best to adopt modern orthography.