• The Utah, Territorial Militia Records shows his name as "Turston Sympson."  Nauvoo Temple records show him as "Thorson Simpson," and the inscription on his gravestone shows his name as "Thurston Simpson."

  His obituary appears in the "Memories" section of his FamilySearch record.  It confirms that he came to Utah in 1848 with the Heber C. Kimball pioneer company, and he married Mary Sophia Barlin, the daughter of Hans Barlin "of Norway."   (See: https://www.familysearch.org/tree/person/memories/KWJF-BFK)

Heber C. Kimball Company (1848)

• Age at Departure: 39
• Head of Household

Sources

• Early Missionary Database
• Find a Grave (Website)
• Frank Esshom, Pioneers and Prominent Men of Utah (Salt Lake City: Utah Pioneers Book Publishing Company, 1913), 1162.
• Journal History of the Church of Jesus Christ of Latter-day Saints, Supplement after 31 December 1848, 15.
• Utah, Territorial Militia Records, 1849-1877.