Colours of Kharkov Tigers
Most Tigers in the battle of Kharkov were whitewashed, but there was camouflage paint underneath, still visible in places. Tigers of the "Grossdeutschland" division were not whitewashed.
These camouflage colours were stated by Doyle and Jentz to be RAL8000 and RAL7008 [1, see appendix F] . In the 20 years since their book was published, restoration projects have found exactly those colours on two surviving Tigers from the period.
Border's choice of colours
Border's instructions specify two colours for the camouflage on these tanks: RAL6011 and RAL 7028. This cannot possibly be correct.
For one thing, RAL7028 is the well-known colour "Dunkelgelb". This colour was first mandated on 18 February 1943. All Kharkov Tigers had already been delivered to their units by that time. Most of the crews did whitewash those Tigers because of the weather. But it would make no sense to repaint those brown Tigers in a new, slightly different brown.
As for the green colour RAL6011, I am not aware of any German documentation saying that Panzers were ever painted with it.
Border's choice of colours in this kit is not correct according to the historical evidence. We may wonder how they arrived at these colours. I would guess that they copied the colours from the kits of Rye Field, another kit manufacturer. Rye Field seem to be the first firm to use these wrong colours.