Go to Home Depot and pick up some brush and roller cleaner in the paint aisle. Apply it with with some Q-tips and it comes off nice and easy. Be liberal with the application and let it sit for a second. It wrinkles up and you just wipe it off with the Q-tips. Won't damage the rub strip.
I used the flat screw driver to do my front and rear bumper rubber strip. it comes of very easy with screw driver.. take your time doing it, then use a cleaner to get the rest of it off...
