US built Merlins were made by Packard not Ford. The Ford factory in Manchester did make lots of Merlins too but they were to the Rolls-Royce design.
Wikipedia only lists the Merlin 32 as using a Coffman starter, as it went into naval aircraft maybe there was a requirement to be able to restart an engine in flight.
I didn't realise that Ford in America turned down the job, that must have been Mr very contrary Ford for you!
I must have gleaned that 'fact' regarding the Rolls Royce blueprints being no good for Ford from the History Channel. I do wonder though about how much Ford thinking influenced Rolls Royce and their shadow factories elsewhere in England, where they did use relatively untrained staff to crank out the volume.
Wikipedia only lists the Merlin 32 as using a Coffman starter, as it went into naval aircraft maybe there was a requirement to be able to restart an engine in flight.