Note direction of bogie wheel arms as this is not indicated in the instructions.
The raised central section should face the top
Updates added to bogies 1. A hole with raised lip should be added on both sides of the main bogie
I added these by drilling a small hole and adding the lip from thin wire. 2. Four hex bolts added to return roller supports. 3. Four small rivets added to front of bogie arms.
Also note that on some bogie housing covers there are casting numbers,
have an oval hole in the housing and others are plain like the kit parts
you wish to add a bit of variety to your bogies.
Simplified spring units could do with the end mountings reworked
Image of early spring unit (right) for your information