I don't know if its worth mentioning, but I found paraffin is a brilliant engine/gearbox degreaser- cheaper and just as effective as Gunk and similar. After dragging the engine outside, I put the engine on a large piece of scrap cardboard box and used a stiff brush and a combination of parraffin soaked rag with a blunt screwdriver to clean it.
Good results, the original Morris green paint still in good condition. A rubber glove over the dizzy internals kept it dry, it looks semi decent now while its sitting in the garage waiting to go back in (which may be sometime.......!)
Ps 4 litres from Homebase £7.99[frame]

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