Fairly certain, though not 100%, that the Sdkfz 222 was withdrawn from service before the Normandy invasions in favor of other recon vehicles such as the 234, Luchs, Aufklarungspanzers, etc. If any were still in service at that time, they would've been Dunkelgelb with Olive-grun and Rot-braun camo schemes, not Panzer Gray. Panzer Gray was discontinued in Feb. 1943 as a factory applied paint scheme. Internal colors, except for the turret which would be same as the base color, were painted Elfenbein (an off-white/ivory color).
One of the best sources for details on the 222 is Chris (toadman) Hughes site, www.toadmanstankpictures.com . He's produced a full interactive walk-around CD on just the 222 and has plenty of detail shots interior and exterior if you like.