I am an automotive upholsterer. Been doing it well over 20 years.
My job is building fire trucks - the upholstery side of it.
I have done stuff at home, but it is rare that I do that.

I have looked at a lot of jags (XJ's) for sale and
there seems to be quite a few with
the headliner material coming apart.
Mine is/was one of them

Not until I read the shop manual did; I figure out why.
Remove the front seats.
Remove the console
Remove the J shifter
(saved the best for last)
Remove the passenger front door!!

If I had a shop, I would charge dearly.
Very labor intensive, as I have learned.
Or I would remove the back glass
and hope it would not break.
Either way - expensive.

(on LWB XJ's you can sneak it out the back door)
My '95 XJ is not a Long Wheelbase Model

This time I followed the shop manual.
Not as much plastic broke than I thought would break.
The headliner, visors and overhead console have been recovered.
I chose a knit type of headliner material; it is easier to clean.
I have yet to reinstall, due to weather.
Yep, doing this in the driveway. My garage is for my Corvette.

I wish I had pics to post
However, skilled in technology - I am not