The castings supplied in the Model Airways kit have limitations imposed by the casting process, and the detail of the perforated cooling jackets in particular, needs to be replaced to look more true to scale.The solution was provided by the brass photo-etched items supplied by Tom's Modelworks.

Tom's Modelworks

Here the white metal castings are shown next to the brass photoetch sheet which will provide the replacement parts.

This is a Williams Brothers 1/6th scale Spandau kit used as a reference