Managed to find some old info on conversion chart for different model paint manufacturers. See attachment. The site is long gone, but found this site https://resourcesformodellers.wordpress.com/2015/01/02/ww2-german-armour-paints-and-camouflage-colours/
Not had a chance to explore it fully, but looks useful.
Another source of information about German camoflage is a 3 volume series called Panzer Colours by Bruce Culver & Bill Murphy published by Arms And Armour. Its probably no longer in print but I have seen second hand for sale on Amazon.