Rio was always Ryo to my grandparents and others in the west who came from the east and knew no Spanish. It seems to have the general American pronunciation until about WW1.
The Ryo Grande, both the river and the railroad.

Right, Ebbie- Lettuce.

I agree with McGrath, there was (and still is to a degree) little consistency in pronunciation of place names. Since radio and television, pronunciations have become more standardized.