I have removed chrome plating from small parts by soaking them in Acetone. You will need enough Acetone to cover the item you want stripped, not cheap for a bumper, and you need to cover the container so the Acetone will not evaporate. Let it soak for about four hours, and then scrub off the chrome with a "brillo" pad and some more acetone.
The biggest set back with this is the cost of the Acetone and the disposal of the remaining liquid.