panels dye to match.....

ok the interior panels in my el camino are all craped up and i found some new panels but i dont get it why do they only come in gm blue but not the color of the ones already in my car it says i have to dye-to-match how can i dye panels , maybe it means paint i dont know the link is
http://www.elcaminostore.com/catalog-pages/01group.htm#interiortrim78-87 i would really like to get these or some that come in the color to match the ones already in the car. thank you for any help.