You can simply use RIT dye for less than $2 a pack from Wal-Mart, Dollarama, Giant Tiger etc. I used 7 packs to dye all of my carpet inside from greenish-grey to black. One pack fills up about one spray bottle that you spray on the cloth, than vacuume it out, or wipe off the excess with towels, then let it dry. No need to take anything apart from your door. This stuff is capable of slightly dying the plastic/vinyl too, so If you don't want that colored, either tape it or put a light coat of vaseline on the parts you don't want dyed.