Terri, I just took the liberty of searching the Ancestry library edition for records on Earl. I notice that he is in the age group of men who have both WWI and WWII draft registration cards. I personally like those as sources, because they appear to have been completed by the subject himself, in his own hand, and I am inclined to give people credit for being able to spell their own name correctly and know their birth date. In this case, however, in the WWI card Earl reports his DoB as 17 Jul 1897, and in the WWII card as 7/17/1898. I also see that in the SSN application in your image, Earl gives his DoB as 1898, but in the Social Security Death Index, it's shown as 1897. The Social Security records themselves have two different years. So I don't think you'll be able to resolve this without an actual birth record.
I am going to speculate that Earl probably grew up believing he was born in 1897, and his family and friends all committed to 1897 as well. Then at some point he discovered it was an error, and the real year of birth was 1898. So the later records that he helped to create (SSN application, dated 1955, and WWII draft card, dated 1942) say 1898. The earlier WWI draft card, dated 1918, and both the SSDI and the tombstone inscription, created from data provided by the family after his death, say 1897.
I think the best thing you can do at this point is pick one date to list in his profile, but include a full explanation of the inconsistent records in the Bio. Someday you may be able to find an actual birth record, or perhaps a newspaper report of the birth that will resolve the conflict. Good luck!