Between King Pressed Steel, Newton Pressed Steel, Service Engineering,
Boston Auto Tool Co, and Boston Machine Screw Co, there are a few officers, a few addresses, and the shape and construction of the unique sockets and some of the handles in common. I gave up trying to untangle the business relationships and timeline it more precisely, which was good enough at the time for my interest in identifying them, with Todd's help, as a heretofore unrecognized 1920s era geographical and design "grouping". AA still hasn't made all the connections, but is at least now in their King section connecting Newton and King, without giving me or GJ any credit.
If you purchase the B.A.T.Co and B.M.S.Co pieces/partial set, it would be a significant contribution, elidas.
Nice find.