Yes Tony probably the late ones have electrics , it is the same with the lightweight trailers if you look carefully at the Arnhem pictures , none seem to have the bracket spotwelded on the side of the trailer for the light .I have one of these abandonned trailer from Market Garden , and there is no evidence , that there was ever one fitted , my other lightweight trailer has all the fittings for lights and switches , same with 10 cwt trailers , if there is a hole underneath the towing hitch , then all the other electrical fittings are there as well.