NSHR 2017 was a B&O GP38 that was rebuilt into a GP38-2. Externally, it still mostly expresses the features of a straight GP38.
I'm using an old Weaver GP38 for the project, the version with fixed pilots. The fan spacing is accurate to 2017.
I've already done a lot of roof work on it, especially around the dynamic brakes. Quite a bit had to be changed, and was done so through a mix of 3D printing and careful putty work.
It took a lot of time and a lot of patience, but I was able to get the 3D printed areas perfectly smooth between puttying and sanding/filing. I'm sure it will pay off when the area has a nice even coat of paint on it.
Thanks for all the responses.