Can I just say...... I have been looking at this puzzle since just after I started caching back in 2009. At that point there was less than 300 active puzzle type caches in Victoria (there are now 915 of which I have found 151 and own 4).
My obsession with puzzle caches started with the second puzzle cache that I found, which was a 16*16 sudoku puzzle (as apposed to the usual 9*9), I'd been working on solving it for WEEKS. I even had neil helping. One Sunday afternoon in August 2009, Neil and I were both sitting round working on this puzzle when I finally had a breakthrough and got the co-ords out. It was fairly late on a sunny but cool day. I was able to persuade Neil we should go out and get it straight away. It still remember the excited feeling!! I had solved it, we rode to the location, took a stroll, hunted around and found the cache, all that work paid off, it was sooooo much more satisfying than a 'traditional' cache. I was hooked.
This first puzzle success had me looking at others around Melbourne, and I found the one above. I had no idea what to do with it. I looked at it again and again over the next little while (few years). I was given a tiny pointer a while ago, which didn't help.... oh no!! What to do!! A cache 51 other people have been able to solve (or have had the answer told to them) and 48 of those had been since I have been trying to solve it.
Today, I finally found the tool I needed on the interwebs (had to use the way back machine - accessible!!) and with some stuffing around FINALLY got the answer. I want to go now and get it!! Oh well, add it to the list of 70 odd other caches I have solved and are waiting for me to visit!