How do you take an SVX sunroof off?

[Ziggy]

Anyone taken an SVX sunroof off?
I need to remove mine to have a few minor rust areas fixed and repainted before they get worse - but it looks like a major!
What went on must come off somehow, but I can't see what to undo or how to approach it.
Mine is a 95 SVX - with a factory electric sunroof which first pops up at the rear and rolls back just a little and stops. Then when you push the button again it rolls back all the way. Still doesn't reveal any obvious means of removal. . .