They look fine just the way they are, trust me you don't want to go much darker than that as I have been pulled over twice for mine and it's a big hassle. Mine aren't even as dark as most I have seen, but for some damn reason Texas State Troopers are bored as hell because both times I was pulled over for just the tail lights being smoked. Both times I was pulled over it was in the day time, once was around 10AM and once was around 1PM.

I don't know if it helps, but every since I got pulled over the second time I started turning my parking lights on when I get in my truck and I haven't been pulled over again for it, probably a coincidence, but what ever I think they look great the way they are Allen.