Some pictures now to hand. First, the car is now on the steel jig ....
The jig was made for a Fulvia Coupe so the subframe that forms part of it fits my sedan at the front but the uprights that attach to the rear spring hangers fall short of the sedan's longer wheelbase so the rear of the car is on jacks for now both for this reason and because ....
In talking to Bill he mentioned somewhat ominously that additional work had been found necessary to the rear chassis rail spring hangers area and was already in hand.

So it seems, out have come the spring hangers along with some of the boot floor and a bit around the area of the rear suspension bump stop ...

On reflection (and not having seen the car for many months now) I realised that this development helpfully closes off my concern that I would get the car back with all the agreed work done (mainly cosmetic exterior panel work) but still requiring patches to less obvious areas that I had not included in the agreed price. As it would be expensive for me to commission/persuade someone else to start on this work afresh, it is actually a blessing (and very reassuring) that Bill and Mark have identified and addressed this work too. It will stand to me in the long run.
As they say ...you couldn't pay to have this sort of work done, but it seems that I am.