I've made that same mistake many times Mike, when you see something you want you have to make a decision there and then and buy them, they are invariably gone when you go back later. We all do it though! I needed a matching set of four and managed to collect three old ones over a period of a few years but a fourth one has always eluded me. It would have cost a few quid to have the old ones replated so buying four already done was a reasonable option. I don't know if the ones I just bought are repro or old ones refurbished but either way the dimensions are identical to the old corroded ones I have. Even the reverse side is the same, no makers markings. My three old ones were all found at autojumbles as opposed to boilerfests so I'm not sure I subscribe to your theory Mike but who knows!

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Regards the fitting of them, I can see now how they were meant to fit, by and large they would have gone onto thin metal body work so the mesh would have gone on from behind and held there by a washer over the studs. My problem was fitting them to a much thicker material, fiberglass. Anyway, I'm pretty chuffed with them The old ones are now on evilbay.