Wiring in hazard lights aka 4-way flashers is a good thing if you don't have them. In the '60s, before they were standard equipment, you used to be able to go to the auto parts store and get a kit wired onto the back of a big red lighted knob that attached to all the wires. Now you are on your own.
But I posted a list of the lighting rules a couple of years ago. The one I remember because people like to ignore it is that the red and yellow flashing lights are too high above the pavement to be converted to turn signals, and probably brake lights, too.
I would have to do a search, but I think the limit was about 80 inches above the roadway.
Someone said "Making good decisions comes from experience, experience comes from bad decisions." I say there are three kinds of people: those who learn from their mistakes, those who learn from the mistakes of others, and those who never learn.