Michael;
Ref: page 156, regarding Currie's tank and as Chris as added, Currie's tank was named 'CLANKY' (page 179).
Ref: "C" Sqn Tac Signs - looks like they were either (within the circle):
1) painted in (hand or stencil)
2) chalked in (see page 127)
3) not used at all
Looks like "C" Sqn just used numbers, no letters, ie: 42 not C42.
Ref: W.D. Numbers, haven't got a clue, although there is a colour illustration, page 180, showing CT 236656, as being used.
Thats about it Michael.