The sources I have all say there is no definitive documentation about what the colors were. The Warship Pictorial 36 book speculates they were various shades of gray. The ShipCraft book shows a model by Kostas Katseas also in somewhat neutral shades of gray. The kit instructions suggest WEM Colourcoats paints KM 07, KM 08, and KM 09. The Snyder and Short paint chips show these as very bluish grays, much more blue than the other two references show.
So I am looking for opinions here, about which way I should go. Should I stay more neutral, or go with the blue gray (blaugrau) hues?
John Snyder, the S&S paint chip lists these as Norwegian colors. I would be interested in any more information you could provide about the history of the blaugraus.