From "Caronia: Legacy of a Pretty Sister" - David F Hutchings.

The liner's launch colour of one shade of green was apparently the original finished scheme, but a graded colouring was later (during fitting out- my comment) adopted to give the ship a tapered look.
The styling of the four shades of green began above the white ribbon of the waterline... The first shade of light green was applied to the main hull and this was terminated by a twelve inch ribbon of darker green which extended around the hull at the level of A Deck. Above the ribbon another shade of green, but lighter than that of the hull was applied up to Boat Deck level. Deckhouses, derrick posts and masts would be painted in an even lighter shade (almost white - my comment).

The Triang was never remotely correct in the colour of its painting and any Caronia model would benefit from an attempt at the final and lifelong 4 greens colour scheme. It is not difficult - just add increasing amounts of white.
It works well.