Car Paint

Is it a bad idea to paint the already existing headliner? we are painting the interior of a friends car and the headliner is a fuzzy gray while the rest of the car is black. we found this vinyl black paint. is it going to go okay if we paint the gray headline with this black vinyl paint? is there a special way to paint it or anything? i was just going to tape off something and start spraying. its not like a thick fuzzy headliner, just a soft material.

Yup no problems using the vinyl paint, just make sure you clean the headliner first of dirt oils etc and you will be sweet