The problem with Rit is that it will always look purple in direct sunlight. Your door panels won't be as noticeable since they are vertical and don't catch as much light.
I tried nearly a dozen applications, but it only gets so dark and never loses that purple hue.
I used this on my leather steering wheel to go from gray to black, but I'm not sure if it works on carpet (Hobby Lobby, Eco Flo, Midnight Black).
