Flocking headliner for a car

[spotonjon]

Hi, got a question about flocking a headliner.

Most headliners are made up think chipboard shapped to suit the car and then covered in a fabric or a carpet.

Just woundering how I would go about flocking this? would I need to get the headliner smooth/shave the carpet back/remove the fabric to flock it?

[Ray (Flock Man)]

Any lumps or bumps will show. The smoother the better.