M-B back in 1939 had a model G-4 6 wheel model http://www.gizmag.com/go/3663/ and from 1930 to March 1944 they produced the model 770 used mostly by the government as state cars, Hitler owned a 770K what was recently auctioned off to some collectors for an undisclosed amount. The Canadian War Museum also has a 770 on display, a good photo of the UniMog http://www.flickr.com/photos/g88ber/5726141432/ and a 1943 L1500a http://www.flickr.com/photos/g88ber/5726141432/