Running board lights for my Cateye

I’ve recently purchased running board lights for my 2003 Silverado 1500. They are meant to stick on to the pinch weld which I don’t have on my truck. I don’t have running boards either or I would attach them there. What other ways could I mount them?

I asked chatgpt just to see what it would say and it recommended to use L brackets to the underside of the rocker panel. Would that work as well?