This cache can help with several challenges. Rhyme Time Challenge, California Multi Cache Challenge, and maybe more.
This is a simple two stage multi. Near GZ you will see a yellow sign with black letters. At the bottom of the sign is a contractor's 6 digit number. Add the 6 digits together to get X. Multiply X by 15 to get Z. Subtract Z from 498 to get N, add Z to 136 to get W.
Final is at N38 03.N and W122 14.W.
Check sum = 55