Welcome to Mosgiel!
We used to always pass this sign as a kid, and I loved it! So I thought it was fully deserving of cache.
From the GZ, you can see the sign in amongst the trees, and across the road there is even a couple benches where you can chill and eat.
GPS signal may be a bit off due to the tree cover, but if you go futher than two trees into the bush, you've gone too far. Cache is a small black-taped about 100mL container. Please cover back up before leaving.
Image Source: http://en.wikipedia.org/wiki/File:Mosgielsign.jpg