I did those extra pics tonight, mainly so they are almost in the same post, but it will be difficult to post them tomorrow.

This one shows the running chassis and the transmission. The torque arm that figured in an earlier post is no longer required. Its job is actually done by the relation of the motor casing with the back of the boiler once the body is seated on the chassis.

Within the firebox, the motor actually sits more vertically than in this photo.

This fuzzy excuse for a photograph shows the smoke box saddle - (fly-cut and milled in tufnol) - and the screw hole in the spectacle plate through which a screw holds the boiler. These two features ensure that the boiler unit sits at the correct height.