I had promised an update today or an overview post of the 1963-1967 Cameo Issue. Unfortunately, the Wilding Issue is taking much longer to get through than I thought. As of today, I expect to complete the 3c value and as the 2c value took a full week to get through, I think this set will take me another 3 weeks to complete - so probably around Christmas.
In the meantime, I will post any new observations that come to light as I continue to list the stamps and plate blocks of this issue. In particular, I am updating my post dealing with the plate blocks of this issue as I examine more and more blocks and new printing order numbers become known. Be sure to go back and re-read this if this topic interests you.
One comment that I can definitely make at this point is that the paper differences that I have written about are becoming more and more pronounced as I examine more and more blocks. Also, I am finding that many plate positions have characteristics with regard to paper texture and position dots that seem to be universal across the plate number. For example, there are some blocks of the 2c that have no position dots on any of the positions, while there are other plate numbers that seem to only exist on ribbed paper and others that exist only on smooth paper. On some of the 3c lower left positions, I am finding two position dots instead of the usual one and on the later printings, I am finding the dots in the right selvage, instead of at the bottom, which is in keeping with what I have seen on the post 1958 printings of the 1c and 2c values.
The 3c value presents somewhat of a mystery so far as it does not conform to the 1c and 2c in as much as it only seems to exist on horizontal wove paper. Also it is the only value that is found in plate block form with Winnipeg Tagging. Why this is the case remains a mystery for another philatelist to study and solve.
The gums used on this issue are problematic. There are definite differences between them, but they are hard to describe accurately. Also, it appears that there may be variation within a block, where some stamps in a block have completely smooth gum with no streaks, but then others will have streaky gum. This may mean that the distinction streaky versus smooth my be less meaningful than I first thought. Additional study will be required to resolve this issue.