Thanks, Ashtone. These are helpful - I've searched a lot on Newspapers.com - but have not found articles. I do have the criminal court record for the Liverpool 1878 conviction (which references the Wolverhampton conviction).
I have some evidence of a James and Rebecca McNally involved in similar behavior in Philadelphia, PA. And, to make things more confusing, there was a woman named Kate Armstrong who was a noted pickpocket along the east coast of the US in the 1870s-1890s. She used several aliases, one of which was Rebecca McNally.
https://criminalsrevised.org/132-kate-armstrong/Kate Armstrong doesn't appear to be my RM - the timelines don't reconcile with Armonstrong's activity and RM's presence in Philadelphia, having children and getting them baptized there.
I do think RM engaged in some level of pickpocketing, larceny. In the UK and perhaps in the U.S.