This was one of the best mods to my rover so far. Super easy to get out and it went back in just as easy. I kinda wish I didn't use the truck bed liner but it looks awesome.
There are some holes above the rear gate the are behind the trim that look like they are for the headrest for rear jump seats that may make a good place for a single rack.

 

I pulled the fabric and the sticky foam is covering about 80% of the headliner board, recessed areas like for the moon roofs are pretty clean. The residue in other parts is quite sticky. Someone mentioned a Scotch pad (kitchen sink type) for getting it off. Will the paint stick if the sticky residue is there or do I need to remove that as well and how to do it without damaging the HL board surface?

 

I used one of those wet sanding scrubber things from Walmart they are dark green and look like a kitchen scrubber but much beefier. Got it wet...lol, and scrubbed the whole thing, it worked very well. Others have used a pressure washer which I heard is the best way and fastest way, you have to use the general tip. I didn't use the washer cause mine had a little damage to the board so I wanted to take my time and make sure I didn't f it up.

 

Oh yeah you can get those sanding scrubber in the paint section of Walmart by the sand paper

 

I put the headliner board on 2 saw horses to work on. I removed the last trim bits, the mid seat netted storage pieces and center light trim, the fabric came right off. I ended up rubbing most of the foam/glue residue off with the palm of my hand, tipped the board on it's side and gave it a sweeping with a soft broom.

I took a soft shop rag and kept it pretty wet with acetone and rubbed off as much residue as I could, the color of my board is sort of a dark green there are a few small creases in the fiber fabric up near the front corner pockets where the sun visors go but they don't bother me. I let it dry for a few hours outside, our humidity is low thanks to the approaching cold front.

After it felt dry enough, I went through 3 cans of good grey primer. An hour later I began to apply the beige spray paint (Rustoleum) that matches the plastic trim pretty close. I'd rather put on several light coats and the material which is textured does seem to soak it up. 2 coats and it's still rather blotchy. Quitting for the day as the wind has really picked up and I don't want it flying away and getting damaged or stuff falling from trees messing up the paint.