I wanted to use the existing boiler. but I would be relocating the running boards and some other details. I permanently attached some boiler pieces that help hold the air tanks on and filled the holes.
The rear supports were covered with styrene sheet and rivets were added with texture paint.
The first task was to cut off the front piece of the chassis and then shorten and relocate the pilot truck. That was pretty easy, as I just cut off half of the pilot truck.
If you look at the prototype, the boiler sits back a bit - the cab starts at the last wheel. I built some supports for the pilot beam as well as the firebox in the rear.
I painted the new pieces and made new running boards out of styrene sheet.
Looking at this, you can see that the stack is a bit too short, and the cab still needs to be upscaled.