When I look at the diagram, I see the wiring for single and dual headlamps, each with and without daytime running lights (DRL). That makes 4 versions of wiring specifically for the headlights.
Could you take a picture of the front of your coach showing the headlight arrangement? Maybe I’m not understanding what your looking for.
Generally, when it comes to DOT required safety lighting, that is all provided by the chassis builder.
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