I have never owned such a dirty headliner personally, it was a real pain to remove but removal was mainly to get at the roof skin. Mitsubishi used an adhesive on the roof of these cars that collects moisture and rusts. The actual adhesive seems to rust, it comes out in rusty chunks, sitting there it rusts away and then rusts your roof and then it makes its way outside and uglies your paint. The car, as clean as it is underneath was not safe from this. Honestly, in the future the car will get a carbon fibre roof skin, should have just ordered it at this point, looking forward to having to re-do this job in the future to change the roof skin. At this point the whole interior is removed, seats, roll cage, most of the carpet is removed (I will probably just take the whole thing out to clean it), and roof liner. Whoever installed the roll cage wasn't a fan of tape measures, on one side you have access to everything, on the other side everything is very tight to the roof liner and the pillars. Could have moved 1/4" to 3/8" the passenger side and split the difference. Peak Little Green Machine achieved, I am amazed this car doesn't stink like must and cigarettes, honestly pre-cleaning it didn't smell bad at all.