1850 Census: "1850 United States Federal Census" Year: 1850; Census Place: Portland Ward 3, Cumberland, Maine; Roll: 252; Page: 90b Ancestry Sharing Link - Ancestry Record 8054 #9330845 (accessed 21 April 2022) John Simonton (54), Blacksmith, in Portland Ward 3, Cumberland, Maine, USA. Born in Maine.
North America, Family Histories, 1500-2000: "North America, Family Histories, 1500-2000" D > Daughters of the American Revolution > Lineage Book : NSDAR : Volume 150 : 1919 > image 295 of 355 Ancestry Sharing Link - Ancestry Image (accessed 21 April 2022) Rachae McLellan.
Find a Grave, database and images (https://www.findagrave.com/memorial/101711071/john-simonton : accessed 27 June 2022), memorial page for John Simonton (unknown–7 Nov 1851), Find a Grave Memorial ID 101711071, citing Western Cemetery, Portland, Cumberland County, Maine, USA ; Maintained by Linda Scott (contributor 46947088) .
The Find A Grave Memorial ... use your best judgment. But now it's available to people who don't have Ancestry accounts, or access to one.