I've commented before how cool your XJ is and it still is. I'd like to hear more about your headliner, sunvisor and soundbar install. I need to do all the same things. Maybe you could spin off a different thread on it. Either here or NAXJA.
Heres my NAXJA thread..
http://www.naxja.org/forum/showthread.php?t=942417
What do you need, a detailed how to? I still need to finish one sunvisor, could take pics of that... if i can remember to.
EDIT: Dan, heres a little something i typed up for someone doing their headliner awhile back. Hope this helps. The soundbar is basically the same.. just make sure any cut/folded over material overlaps towards the rear of the vehicle so it's less likely to be seen. This may not be an issue with padded material however.
OK, once the headliner is out of the vehicle pull the old material off it. A set of sawhorses and a sheet of plywood make a good work table. A hand holding the headliner is highly recommended as well.
Then you need something to remove all the old foam, i have used a hand brush and vacuum brush attachments with good results. You want to get all that stuff off so you have a clean solid surface to glue the new material down.
Once it's nice and clean lay the new material over the headliner. Position it so you keep your maximum leftover material. You want the material to just overlap on all edges, the rest will be trimmed. Apply something to clamp one end of the material down with... clothes pins worked well for me.
A second hand from here really helps.
Fold back the new material exposing half the headliner... this is where you spray the glue. Practice laying the material back down a few times working from the center out.. trick is to position it the first time so you wont have to try and lift it once it's embedded in glue. Once you feel confident your ready.
Before ya start spraying adhesive a few points..
The adhesive comes out almost like a silly string when nozzle is correctly adjusted, i like the med setting. Watch your overspray as you wont get it off any material you accidentally hit. I like to do this outside as i dont have to worry about floors etc. The temps your working in will affect the setup time of the adhesive. You want it nice and tacky when you lay the material, not WET... you'll see what i'm talking about.
Once you feel ready again fold back the material half way back and make a nice crease. Spray the adhesive on the headliner and material, wait a few minutes letting it tack up, then hit it again, then do it a third time. You want to be liberal with adhesive, not drench it each coat. Then with your assistant slowly lay the material to the headliner working from the center out and to the outside edges. Go slow here and you'll avoid most wrinkles. If your laying it down and feel wet glue coming through stop and let it tack a bit more.
Once you get this far you have the skills. Just repeat for other side. Let it dry nice for a few hours or overnight. Then trim your excess around the edges. Flip it over and take a razor knife to the holes for sunvisors, overhead lights etc.
Remember, take pics along each step.. maybe a third person can snap these. This way you can do a nice writeup for others wanting to do this as well.
Good luck, it's easier than it sounds bud. Take your time and you'll be happy with the results.