What kinda paint was used for the inspection marks on the torsion bars for 73?

[WH23G3G]

What type of paint did the factory use to put the inspection marks on the torsion bars as they came down the line in 73? My torsion bars are original 318 bars, still in nice shape. I cleaned them up to reveal bright yellow inspection marks still visible. On the driver's side it's nicest, it has to daubs of bright yellow paint. The passenger side doesn't really have a daub, it just has spatters of yellow paint. I was wondering what type of paint they would have used to put those on. Because I used Castrol Super Clean degreaser, a lot of it too, to remove the grease and it removed some of the black paint but not the inspection marks. I'm glad too, because I wanted to keep them. It's a cool thing to see, unlike on newer vehicles.

[hemihead]

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