The armoured regiment in 4 CIBG at the start of 1965 was the Fort Garry Horse. I am pretty sure it was replaced as a normal rotation by Lord Strathcona's Horse (Royal Canadians.) In 1965 the Centurions were being upgraded with a suite that included IR searchlight, ranging machine gun and extra armour. I think they already had the extra fuel bustle at the rear of the hull. (One of the projects I had at 4 CIBG HQ was the upgrade of the 75 or so Centurions to about Mk 15 status. As I had trouble spelling tank, I did a lot of study, which is why I can recall a bit of it.)
The tanks were painted in a dark camo pattern with, oddly, the radio antennas painted in a black and white barber pole design. They did not use the Canadian flag as an identifier, but instead used a red square with a gold maple leaf in it. The other identifier was a square with a top right - bottom left divider with yellow and red (I think. Give me a break as it was 45 years ago) as the two colours with a 2 superimposed on it. This identified it as the brigade armoured regiment. I can't recall details of the CFR number and the bridge classification, other than that the latter was a circle with the classification in it.