Some history...
In the US the first production B engine plant was in Rocky Mount, NC (still producing) as a joint venture with Case as described above. Later the Walesborough, IN plant followed in the US to produce the Dodge engine (for several years they were produced in Rocky Mount). Today both plants are building well over a combined total of 1,000 engines a day (4B, 6B & 6C). Also, the engine is built in the UK & Brazil (possibly other locations in the world). Some of the newer 4b version QSB (electronic controlled) that are built in Brazil go in the Ford F150 truck and use an HX27 Holset wastegated turbo.
This forum is great because.. If Clessie was still alive today I believe he would be very proud of all of the conversions! Cummins is the only independent diesel engine manufacturer that remains in the US that is not currently owned by a truck/auto manufacturer in some form. There is a long tradition of conversions and it all started that Christmas day in 1929 when Clessie pulled up in a 1925 Packard that he converted and convinced Mr Miller to keep funding the business in Columbus Indiana.