Great stuff Ron M and Thank You, my 'expertise' I am afraid starts and ends with Sailing on two vessels fitted with Doxfords, from reading other contributions on this site there are members who are more expert on Doxfords than I. It is certainly possible that the Doxford engine was built by another company, Harland & Wolff of Belfast built B&W engines and then after Test Bed Trials deconstructed the Units for reconstruction at the Shipyard building the vessel using local labour under the watchful eyes of a H&W Guarantee Chief who sailed on both Trials.
Doxford in their early days when trying to convince Shipowners to change from Steam to Diesel (Diesel Enginerooms costing 50% more) went to great lengths to secure a Sale, not only did the Doxford Engineer do both Trials but stayed on the vessel for a year to work on the M.E. if required and of course report any problems to H.O. There were other incentives offered offered by Doxfords but some Shipowners were not convinced and were still ordering Triple Expansions with L.P. Turbines well into the 1950's built on the Wear including my very own 'Baron Ardrossan'.