One day I learned something very important about life!
When playing this game as a child, at times the other person would make a mistake or two with the little black and white pegs. I would become frustrated, because this would make it unsolvable.
When computers came along I thought it was great. I could play without the other person making any mistakes. This made every attempt solvable. ... But I discovered that this wasn't as interesting, memorable, fulfilling, or rewarding.
That day I learned a fundamental feature about being human - we have flaws. While sometimes that may make life frustrating, it also adds interest and memories to life. For example, many of the videos shared on the internet are not of things going right, but of moments that things turned out badly. When I listen to labourers telling stories at the pub, or women sharing their week, they don't talk about the days everything went perfect. They talk about the times things went wrong ... badly wrong (either for them or someone else). Many video clips we watch have the same vein. These are the adventures of life! It could be the time:
- they bogged a header, a truck and a tractor all in the same day.
- the rope on their load snapped and everything went all over the road.
- a crane taking a car out of the ocean overbalanced and also fell into the sea.
- a fisherman put a huge hook through his finger.
- a truck driver tried going under a bridge too low for his load.
- they couldn’t find their wallet/purse … until they looked in the freezer.
- they accidentally made a banana cake with plain flour - and ended up with a banana slice.
Out of all that happens in our life, those are often the moments and days we remember. That is what makes an ordinary, mundane life interesting.
We are not perfect, we are human, and that's what makes life an adventure.
So if you have trouble with this puzzle 
, don't worry, you're only human. I know that you ARE GREAT at something else! 
Celebrate that and enjoy your adventure. 
The cache
Solve the code and you will have the last three digits to the South and East Co-ordinates.
This is meant to be a bit of a challenge for the masterminds out there. If you don't remember, a black peg in the right hand box means one of the other coloured pegs is the right colour AND in the right spot. A white peg in the right hand box means one of them is the right colour, but in the wrong spot. (After feedback from previous finders, I've changed the contrast on the image to make it easier to see.)
Generally, I start with trying to work out the colours first, then the positions. All the best. 
P.S. be aware that at GZ you may be highly visible from a room at the end of a nearby building. (I know this because I saw people working there while I was taking co-ordinates.)
You can check your answers for this puzzle on GeoChecker.com.