What a tantalizing subject!
Gene Gurney, in "A Photographic History of the US Army" (Crown, NY, 1977), on page 8 says writing of the F&I period, "certain colonial units were made part of the British regular establishment." I'm not sure how authorative he is but it seems there was a home in the Brit RA for colonials.
I erred in saying the Rangers were Brit RA. They were "provincials", on extended duty but not part of the permanent establishment.
My next stop is Francis Parkman. In "France and England in North America" he gives some order of battle information.
James B. Ronan II
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