good research theirpuppet !

I'm not sure where you can fit 50 to 60m of ramp (both directions) without removing the Smith's extension. Can you sketch something?

As I see it, if the ramp extended further into, er, devonshire rd, then it would start to block pedestrian flow and block access to the restricted side road to the back of the dartmouth arms.
Also the able bodied will not want a 50m detour - they'll want the stairs as well.

Remove the Smiths extension and a 50m straight ramp for all just about fits.

The main problem is that fantastic artwork that adorns the brickwork will be buried. (Cue 20 page thread on merits of this work...).