Thanks Rick for your help. It was good to have my view of the thing confirmed. As to the vendor, we have agreed to disagree--I'm sending the bumper back to him. He kept insisting that I was making a big deal out of it, that the "brackets" to which the back-up lights were attached were somehow detachable from the bumper. For the life of me, I could not see how, unless you broke the weld. I asked him, repeatedly, how these "brackets" were attached, if not by a weld; he had no answer, only lots of anger. It is obvious to me now that the brackets had simply rotted off on the bumper he sent me--it had other signs of rot, such as a rust hole clear through, that he had also not mentioned prior to me sending my check.
Anyway, to go out in the cold to help me out was above and beyond. Thanks much.
404 N. Willis Avenue
Champaign, Illinois 61821