Hi Tanksparky,
I trawled through the good old internet sometime ago and found some good info on panzer colours written by George Parada on
http://www.Achtungpanzer.com" onclick="window.open(this.href);return false;, the bit on the late war is summarised below:
"August 1944, RAL 7028 dark yellow factory applied as base colour, with RAL 6003 dark olive green and RAL 8017 red brown as camouflage. In addition small yellow, light grey or white applied to green and brown camouflage areas, with small green spots on dark yellow areas. Known as “ambush” scheme, used on Panthers and King Tigers.
October 31st 1944 RAL 8012 red oxide new base colour, RAL 7028 dark yellow or RAL 6006 field grey and RAL 8017 red brown as camouflage.
November 30th 1944 RAL 6003 dark olive green as base colour, RAL 7028 and RAL 8017 red brown as camouflage. Sometimes RAL 8017 replaced with RAL 8012 red, also RAL 6003 replaced with RAL 6002 dark green.
Due to shortages some vehicles only painted with RAL 7028 dark yellow.
Early 1945, RAL 7028 dark yellow is base colour, with RAL 8017 red brown and RAL 6003 olive green as camouflage.
All schemes from October 1944 were factory applied, hard edged schemes, disruptive edges sometimes defined in RAL 9002 white.
Interiors painted RAL 1001 light cream or could be RAL 9002 off white, late war RAL 7028 dark yellow used. Inside of hatches painted with exterior base colour of the time.
From August 1944 King Tiger interiors left in red oxide primer to simplify production.
During winter white applied over camouflage and washed off afterwards."
As for Tamiya equivalent for red oxide, not sure as I use Vallejo acrylics, Model Colour 982, I can't find a Tamiya reference for this in any of the charts I use, and as Dietrich mentions colours would vary in the field, the OKH orders would be modified depending on what was available anyway. I don't think there is any right or wrong with colours, if it looks right to you then it probably is!
Hope some of this helps!
Steve