With the abutment built, the next challenge is getting the wing wall lengths measured.
Using Google maps, the approximate length was ascertained reasonably well at the10m scale and by comparing this with the bridge dimensions I obtained earlier.

Both the Eastern wing wall lengths being shorter due to the rise in the road/terrain appear as a nearly identical mirror image on either side along with the end height.
On the opposite West wing, both walls are the same in length but wall end heights match the prototype embankment profiles either side of the bridge.
The ends are 6mm lower in height to that of the abutments due to Coal Road rising toward the bridge.
All walls are angled at 80° for the retaining wall lean, offset at 6°, which is 96° to the bridge horizontal length.

These measurements are as accurate as one can get using photographic images so are representative for my modelling purposes. The majority of the S & C bridges have capped column structures at the end of the wing walls that ‘anchor’ the structures into the terrain, that for the life of me I can’t find a name for, unlike pilaster, pier, parapet etc.

Looking at my photos I see that I may need to correct the Wills kit end plates again to get the bridge sitting on the abutments as per the prototype. Enjoy your celebrations in the meantime.