Today I received a package from Mr. Muffins containing the MTH Premier unpowered B unit to go with the PS3 Bessemer and Lake Erie F7 A unit I bought a couple months ago also from Mr. Muffins. The B&LE ran an F7 A-B combination on the Kaylor Branch (former Western Allegheny Railway) into the 1990s. They did this because of the sharp curves. I took several color slides back in the film days, knowing it wouldn't be long on the rails. The B&LE main line is about a mile from my current home.
BTW These are the only engines I have that I bought new. Everything else was bought used, most from OGR Forum members.
Here they are.