Question: Locomotives kept grand trunk lettering for service in the U.s on railroads such as this known as st-laurent et atlantique quebec? 
Sentence (from "St. Lawrence and Atlantic Railroad"): The St. Lawrence and Atlantic Railroad (reporting mark SLR) , known as St-Laurent et Atlantique Quebec (reporting mark SLQ) in Canada, is a short line railway operating between Portland, Maine, on the Atlantic Ocean and Montreal, Quebec, on the St. Lawrence River.
Relevant evidence: Yes