steptoe: I no longer get into the city as I used to for work, I would get in there ever few months, and now have not been in the area for a few years.
Unfortunately that means I am going to have to assume this has gone astray (or been carried off by ants as a mobile home) and archive it.
For those who never worked out the code - the first letter of each word gave a number based on that letters position in the title
C=1
o=2 (ignore 2nd o)
k=3 etc
Hope you enjoyed it folks, and now someone else can place a cache in the vicinity.