As the Molly Ann is not based on any particular real-life locomotive I have free range on colour scheme.
However, I have a soft spot for all things GWR so started looking for design ideas.
I have arrived on the 1361 class locomotives. GWR 1361
They were built to work on branch lines and in the mineral works of Cornwall my favourite part of the country and another good reason to base Molly Ann on this locomotive.