Please do not go to the given coordinates. There is nothing there to find.
But, if you could step back in time to June 26, 1950, you would be standing at the base of the screen of the Texas Drive In and would be able to watch the very frist drive in movie shown in Taylor Texas "Canyon Passage".
To obtain the coordinates for the final bonus cache, use the clues from the Lab Cache and the coordinates:
N 30 34.ABB, W 97 26.CDE