Thank you for making this guide. I just used it for my 2021 Badlands.
For others:
I found that cutting the rubber hose near the clip (on the drivers side of the clip) that attaches it to the grill is a good spot to cut it. Then when you have the cut piece in your hand, cut a little bit more off because your new check valve will occupy some space in the line.
Also when reassembling everything make sure ALL your screw holes line up perfectly before you start screwing.
installed check valve on mine, leaks are gone! I didn't zip tie, I also didn't cut any of the hose, there is a bend in it now, but no kinks, no leaks, hopefully it lasts.