i believe you are right, the rotor box looks very farmersboy. i have a lot of farmers boy paperwork in the office, so will have a look, when i get home, as working near sherborne, dorset at the moment. should be home in a month or so!
I managed to get 6 tins from the rep when they discontinued it. It’s exactly the right colour blue for the later autoculto implements, but know I will have problems replacing it.
this was at the last cheffins, sutton sale, and definately home made. only drives onn one axle, and the wheels were bolted to the remains of the mgdrive wheels