Charlie's Sterling Service was on the southeast corner of 14th and Merchant Streets at 1398 Merchant Street.
In the 1960s, Sala's Quaker State Service operated at that location. [update July 28, 2014: Sala's Quaker State was owned by Irvin "Buss" Sala who operated the station until 1982 when he retired.]
Currently, it does not appear as though the building is being used as a business.
Nancy Bohinsky Knisley grew up in Ambridge in the 1950s and 1960s. She is the author of Ambridge Memories, a blog dedicated to local history from 1950 to 1970. Visit ambridgememories.blogspot.com for more.