A somewhat trivial alert but nonetheless a nuisance. The tubulars that support the front bumpers have upswept support bars with a clamp at each end when loosened the supports can be adjusted in order to raise or lower the bumper slightly. Looks like a simple clamp at the front end until one loosens the clamp bolt and inserts a screwdriver in the gap to "spring" the clamp. Whereupon the clamp splits apart into two broken bits. It turned out to be a casting and it certainly wouldn't spring. My problem was primarily caused by the assembly having been powder coated which increased the adjacent tube thickness.
But watch out - a seemingly simple job bites back.