I've now made a start on building the third Clayton prototype. I'm still waiting on the etched parts to arrive (they've been posted so blame Royal Mail) so while I can't start on the body yet I can get to work on most of the mechanical aspects.
One of the main changes from both my approach to designing the Hudson-Hunslet and the first Clayton prototype was the decision to use a keeper plate and to assemble all the drive components outside the model. This means I can put together the layshaft and the wheelsets in comfort without having to try and fit everything together inside the body.
Compared with trying to fit gears inside a body this is so easy that I'm never going back to the old approach unless forced to do so for some reason.