Dash Oil and Brake Warning light - how are they triggered in the start function?

You are correct. And it IS supposed to illuminate during crank to show you the circuit is functional.

67dart273 means well but doesn’t know and is clouding the issue and putting this thread off topic.
RE read what I said. YOU are the one who "doesn't have time" to look it up.

There are ONLY two power sources, from the switch----IGN1 and IGN2, PERIOD. If you do not understand how they function, you need to SPEND THE TIME with an ignition switch and figure that out, or else don't come on here and argue that someone is wrong.