According to the box,this kit complies with the Gauge O Guild Code of Practise CP1 for the content and quality of model railway equipment kits.
Interesting. The code presumably doesn't cover holes for wheelbearings then. These are 2mm oversize.
Undersize I can deal with. Oversize is more tricky involving lots of soldering, poking, soldering and checking to make sure the thing will sit flat.
This is after I find the minimal instructions mention that the original design has the buffers sit 4mm too high in an effort to get the model around 6 foot curves. An alternative construction method is suggested to sort this out but I couldn't make much sense of it.
Finally, the sideframes - soldering these in place is fine if you don't mind trapping the wheels.
So, I'll work out my own pivot arrangements and have provided a large area for the sideframes to be glued in place after the wheels go in and painting.
The second bogie should be much quicker to build...