Most, if not all, of the brand-new MBT's for the Ardennes Offensive left the factories in overall red-brown primer with patches of green and yellow. And in the case of some of the Tiger ll's of s.SS Pz. Abt. 501, ambush spots over that same color-scheme. (Note that it seems that only tanks with a hard-edged camo job recieved the ambush spots. Those with a soft-edged {as in air-brushed} job didn't seem to recieve the spots). There is at least one pic of a Panther in a base color of green with another camo color applied. AFV's built in foreign countries, such as the Hetzer in Czechoslovakia, were finished with stocks of local national colors, which varied from the German colors. Getting back to the Ardennes, older vehicles retained their original paint jobs, so that in a single unit you might see several different vehicles all with very different camo schemes. With your choice of vehicles, overall German yellow would work, with a lot of dirt, chipped paint, and wear spots.