I've now painted the 'lid' with a mixture of black and grey to represent roofing felt. The second coat of 80, matt grass green, has been applied thinly over the body, allowing the blue and the wood to show through. The hinges and handles have been lightly brushed with 70, matt brick red, which I always to use to portray old rusted metal. Then a very light light brushing of matt black has been wafted over to tone it down.
I assuming batteries and a heavy duty motor so do you think there would be any external signs, on the bodywork, of their internal presence?