Noel, the various colour albums should show enough of them to get an idea.
Basically, for A and C classes:
1. New - to early 1960s at latest: All over silver, bogies & roof included when new. Since this weathered worse than any livery in history, before or since, heavy weathering is obligatory to look realistic! Numbers in light green in ends and on mid sides. Metal Flying Snails light green attached, not just painted on. I have one somewhere.
2. 1960 or so, overlapping (dirty) silver, to 1963 - post-'55 lighter green with or without thin waistline light green band. Steel "snail" painted light green attached to sides, high up middle. Numbers in light green on ends and sides as before.
3. 1962: now we're into the black'n'tan era. Initially, full black'n'tan with waist high tan all round. Numbers on ends as before but in white. Side numbers small at ends. Then, all black. Some had CIE rounded on sides with small numbers at cab ends, others had a single large number in the middle and no roundel. Numbers on all black ends as before. Finally, some (not all) got the yellow panel with black number; other details as before.
4. After re-engining (if that's a real word) in late 60s / early 70s, a few initially with full height tan band, but most (and eventually all) with lower dipped tan band on side. Roundels and smaller numerals.
5. Post 1972, Supertrain livery.
6. For the A class, post-1987 Tippex livery. No Cs ever got this as they were all recently withdrawn. I think a C in tippex would have looked great!
Re the grey / green era, there will be a book.................though it's going to be several years!