Bumper guard mystery

Guy,
I too have a pair of the two rib bumper guards you describe. They fit my front bumper blades perfectly, although my front blades are reproductions from Stan in Wellington Kansas. I have never tried them on the rear bumper, but I'm guessing they won't fit because the front blades seem much flatter than the rears. One of the two three rib guards I am going to use on the rear bumper has the flatter shaped cutout in it, so I assume there were two different guards, one fit the front bumper and one fit the rear bumper. (I know the two guards I'm going to use on the rear bumper are authentic Cord guards.) I'm planning to trim the one three rib guard to make it fit the rear bumper before I send It for chrome. This will give me two each. Problem solved.
Hope this helps,
Curt

Could somebody school me on bumper guards please? Two pairs of bumper guards came with my Westchester, wrapped in paper, fresh from being re-chromed. All appear to be original period bumper guards - not later reproduction. Yesterday I attempted to fit them to my original and correct bumpers. One pair has only two horizontal ribs and the other has the usual three. The first three rib I mounted fit perfectly, but the second three rib and both the two rib guards have a considerable gap showing where they are cut out to fit the contour of the bumper. They are far from flush fitting - I would say there is well over 1/4" of daylight showing at the apex of the bumper guard where it is meant to sit flush with the bumper blade.

Are there different curvature bumpers through production? Are the two rib bumper guards an oddity or rarity? Did any other manufacturer use these style bumper guards? They do not look like production Hupmobile or Graham bumper guards but a look at a photo of the Hupp Junior Six prototype shows a much more curved bumper blade than the Cord bumpers with Cord like bumper guards. Any help in solving this mystery would be much appreciated.