I used one can of the 3M on my liner (from the sunroof back ) .
The stuff as mentioned works great and the spray is very controlled .
I used a shop vac to take off the 1st layer of the liner that turned to a
powdery dust . and just rubbed a brush against the rest of it.
I did it in 2 sections .1st section was from the sunroof back to the
2 plastic plugs . This gives you a start and stop point ,because you are suppose to spray both surfaces ( also this helps so you don't overspray
one and not the other ).
Also used a 1X2 - 36 " long clamped to the sunroof and fabric to hold it in place . Hope this helps .