This is a successor to Loose Caboose Gets Smart (GCQ6A5), a cache that was here from August 2005 to December 2016.
From the original listing: “This caboose started work bringing up the rear for the Atlantic Coast Line. In 1967, Atlantic Coast Lines merged with Seaboard Airline to form 'Seaboard Coast Line'. The infamous caboose jumped track from ACL to SCL sometime soon after. The SCL railway was in business until 1980. Built in 1915, the final resting spot of this great car is the Umatilla Library, formerly used as a depot for the Atlantic Coast Line.”
You are looking for a lock & lock. The high terrain rating is for going beneath the caboose.