I found Aquanil-X, CroftgateUSA's waterless car wash works. Wipe seals with it, and haven't much problem with it since. Aquanil-X restores the rubber as well, and protects from weathering.
Sticker remover takes off the black streaks without rubbing, but don't let it get on the decals.
http://croftgateusa.com/buy-croftgat...ss-car-washing