How to take a Convertible roof off

It is time to change the well worn roof on my XJS convertible, and as it is at the paint shop for a respray we thought we’d take it off now (means we can tackle the rust around the bottom edge easier too).

We cannot find any instructions anywhere on how to do this, no pictures or guides, so it is taking a lot longer to do than it should.

If anyone could help, point us in the right direction or supply information and pictures here it would be greatly appreciated

Thanks,

Laurence