The bomb was eventually defused by the Royal Army Ordinance Corps of Hereford. It was a duffle bag bomb. Here's a photo of it near the ramp. Viv.I think the building line is now the outer edge of the paved are of the Queens Hotel access area, and it was the Ikon Gallery that was damaged in the 1974 bomb blast. The Royal navy & Royal Marines recruiting office was next door.
To me it looks like the overhang (of what was the Palisades) might be the only part of the building exceeding the original footprint of Queen's Hotel, while the shops at street level remain within the Queen's Hotel footprint.