Getting there; indeed nearly finished:

A cab roof was made up from cardboard tube, rolled with a rolling pin to the correct radius.

Safety valve covers were fabricated from a sheet of 0.5mm plastic; two laminations for the base and three for the covers; with a length of thin wire glued around the top edge to form a fairing.

This same thin wire was used for the cab handrails and the smokebox door dart.

I think that the largest job still to do now, if you ignore the painting and lining, is to build some steps for the running plate.