The cache is a medium size green ammo box. Once you get near the coordinates I'm sure you'll realize where our maniacal minds thought to hide it.
IMPORTANT: YOU WILL NOT NEED TO STOP ON THE HIGHWAY TO FIND THIS CACHE. IN FACT I HIGHLY ADVISE AGAINST STOPPING ON THE HIGHWAY. FIND A SURFACE ROAD, THINK OUTSIDE THE BOX. DON'T GO NEAR THE HIGHWAY, STUPID.
I'm not going to list the contents, and I'm not going to tell you which path to choose (this comment will become clear when you get there).
The hint below will tell you some "specialty equipment" which is not NECESSARY to success, but may make your life a bit easier.
Taz
Wile E. Coyote
Babs