First... Let me apologize if the coordinates are off. I was having a hard time with a jumpy GPS. And this locaion is new enough that it doesin't show up on Sattelite Photos yet.
Search the southeast corner of the Caboose. You are looking for a small, colorful container with room for small swag.
Please replace it as you found it.
It is accessible from the pavement, but feel free to climb around and explore.
Sidenote: This Caboose is currently part of the Adventure Lab - Caboose Tour fo Northwest Arkansas. But, the icon to start this Adventure Tour is on your map about 8 miles SouthWest of here, near Cave Springs. Use the Geocaching Adventure Lab App to expore this caboose as part of that tour and collect an additional find.