Better talk to your plater before welding on your bumper .We did my son's truck bumper that way .One place said we won't touch it. The other one wanted like $700 to $800 for plating just because they had to work 4 welded bolt holes and you did a nice job, he said . I said no thanks ! If you are painting it I no problem . I cut the rounded head off, welded the square part in the hole ,ground smooth,then put a large washer on the back side and welded it solid .