In the log book of some of the caches you will find a number for part of the oc-ords for the final Bonus cache up at the mina area.
The Golden Cross mine is open to the public in the day time and the gates near the start of the mine area are locked at night.
Bring the family and go for a walk around the mine area and find some other caches at the same time.
Mind out for other cars on the road when you stop to find the cache.