Paint color question

As I disassembled the front end, specifically the steering gear on my dart, I discovered some parts painted yellow or having yellow paint marks? The bolt heads that hold the steering gear to the k frame were yellow along with the nut that holds pitman arm on. Is this factory paint colors?
Thanks

I've got the same type of yellow markings here and there under the hood on my car. Aliens. That's what I think. They're inventorying our a bodies for the big day. But I'm not positive.