A simple offset multi. At the waypoint, you will find an information sign about the history of the park. On the southern sign (the one facing the street) near the bottom, you will find a line starting with the number 0 and ending with the number 1.
Using the three digit number (ABC representing that number) found between those two numbers, do the following:
S 33° 53. (subtract ABC from 968 to get the final location)
E 151° 08. (add ABC to 152 to get the final location).
The cache is in plain sight. Do not poke, prod or dismantle anything.