My best guess, It looks like someone did some "rattle can" red oxide paint where maybe there was some rust. I noticed that under the door guide and on the rocker, lower fenders and such. Looks like the same red oxide on the half shafts and clutch cylinder. Probably to prevent surface rust.
I have a 10,000 mile car here and I believe the half shafts are (or were) cad plated. Where I have cleaned a spot they have that yellow tinge that resembles cad plating, not sure if that is correct either.
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