I just got around to doing this and couldn't notice much difference between 75% and 100% (no flickering, though), so I just went back to 75%. It appears that it's not just the DRL that's brighter, but also when just parking lights are on, or headlights as well. The amber surround is just perma-brighter, now, and that's great by me!
I want to say that whenever I would have been on DRL prior to this mod, it was definitely brighter than when on parking lights/headlights. It was turn-signal bright when just DRL before the change to "4B". That said, I didn't start the truck and go into any gear/neutral cuz I wasn't going anywhere at this moment. I will be soon and will do my normal testing of signals in front of the windows when I leave. Regardless, a huge difference over the factory's 10%. If it was brighter then and still brighter now, then I guess I just made everything else involving the amber surround outside of DRL brighter. Was that the point of this? Maybe I understood it wrong, though either way, I'm good with the change for sure.
@Antho do you know of a way to increase the brightness of the rear tail surround as well? As far as I could tell, that didn't change along with the DRL (cuz it's
not the DRL, presumably), but ya never know...
EDIT: Here's parking lights before @10% and @75% settings.
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