Is this the same Gunnar Ivar Sundholm who was naturalized in 1923 in New York? The only conflict is the birth month: 30 September 1886; i.e. exactly two months after the date in this profile.
Also a Social Security Death Index Record:
Date of Death: December 1965
Est. Age at Death: 79 years, 2 months
Last known residence: Voluntown; Glasgo, New London, Connecticut