I just happened to come across this thread and I have an answer for you (although your question is a year + old!) The Sherwin Williams equivalent to Benjamin Moore's Manchester Tan is "Wool Skein" SW-6148. Benn2517 is correct that you can always color match, but I personally like to know the "equal" if one exists! :) In the photo above, it's SW Wool Skein.
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Exterior dark trim
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