Having set out my 35 footer in the parking areas at several parks and/or monuments (including the Bison Range) in order to drive the sites, I think you are underestimating the NPS personnel. Most of them understand RVs well.
Formerly posting as "littleblackdog"
Martha, Allen, & Blackjack
2006 Chevy 3500 D/A LB SRW, RVND 7710
Previously: 2008 Titanium 30E35SA. Currently no trailer due to age & mobility problems. Very sad!
"Real Jeeps have round headlights"