It can be confusing but be aware that the Red Rock Pass (or America the Beautiful) does not cover all trailheads or places you may want to visit. You need to pay a separate fee for Red Rock Crossing (Crescent Moon), Grasshopper Point and Slide Rock, West Fork (Call O'Canyon).
I believe the Ranger Station/Visitor's Center is still closed so don't head there for a hang tag - do as CDR suggested and just lay on your dashboard. Also the hang tags tend to melt in high heat if you are on a long-isn hike :)
Last summer we did a trip and put our park pass in the hang tag. Came back and the hang tag had started to melt and twisted our park pass into a wave. The pass was ok, but it will never lay flat again. We haven't had that problem just leaving it on the dash.
We used our America the Beautiful pass a lot in Sedona and hung it on the mirror. The Coconino Forest ranger responded to my email originally: The America the Beautiful pass works in lieu of the Red Rocks Recreation area in all places except Call of the Canyon, Crescent Moon, and Grasshopper Point. Have a great trip! Oh, and we did have a rental. No problem.Edited: May 16, 2021, 9:52 pm