Delivering room service in a hotel can be a tough job, as I found out one summer. You've got to keep track of what room is what area of the hotel and who ordered what. Minutes can add up, and time is money, you want to go direct from zone to zone. A further complication here in the Santa Clara Valley is the great numbers of visitors from all over the world who are frequently calling for things from home.
This puzzle doesn't require advanced mathematics or programming ability and there are a lot of hints here. Like the job itself, you need know where to connect. Bring a writing stick and beware of sharp rocks.
Update 1/9/2023: Things have changed around GZ, there's now a fence and a gate separating the site from what looks like a good place to park. Certitude will give you a legal parking place and the new location for the cache. It is only a few feet, the offset is given in the cache page hint as well.
Checksum=52
Congratulations to Chrysalides for the FTF! Its been brought up that there is an ambiguity in the clue for one of the digits. My advice is to never settle for a passing grade but to go for an "A" every time.
You can validate your puzzle solution with certitude.