The Huntington Digital Library has some more Kent Frost photos from his trips through Canyonlands and other southern Utah places. The photos represent two different trips. Most pics are from an October of 1955 jeep excursion, while one photo is from May of 1957.
This first photo from October of 1955 is a great photo that shows Kent and Fern Frost standing in front of a CJ-2A with a Porter & Reed hardtop. I’m not sure if this was one of their jeeps or not.

CREDIT: None …. Caption: Fern and Kent Frost next to a CJ-2A. DATE: Oct. 1955.

CREDIT: J. Ballard Atherton …. Caption: Frost Jeep Party. DATE: Oct. 1955.

CREDIT: Dudziak, Joseph Lawrence …. Caption: Camp of Kent Frost jeep party near Lizard Rock.. DATE: 1957-05-01

CREDIT: J. Ballard Atherton …. Caption: Frost Jeep Party. DATE: Oct. 1955.

CREDIT: J. Ballard Atherton …. Caption: Frost jeep in Needles. DATE: Oct. 1955

CREDIT: J. Ballard Atherton …. Caption: Frost jeep in Needles. DATE: Oct. 1955

CREDIT: None given …. Caption: Marston rides the hool of Kent Frost’s jeep. Needles country, Utah. DATE: Oct. 1955

CREDIT: J. Ballard Atherton …. Caption: Frost Jeep Party. DATE: Oct. 1955.

CREDIT: Otis R. Marston …. Caption: Lunch stop during jeep trip. Head of Dark Canyon. Gin Masland; Kent Frost; Fern Frost; Ballard Atherton; Margaret Marston. DATE: Oct. 1955.