Hello all,
certainly an interesting and difficult project.
Barkers were one of the many coachbuilders that made bodies for your chassis. This was the practice then, the car manufacturer sold the powered chassis then the owner commissioned a coachbuilder to make a body to his requirement. (Not the car maker). I also think that Daimlers would be upset to being compared to Rolls Royce, as they believed that they were better and the car manufacturer of choice of the Royal family.
Alec