Today we have two shots of the MH built M44 155mm Howitzer under test at the Aberdeen proving Grounds in Maryland (are these still there I wonder?)
The first shot shows it mounting an obstacle. The M44s could climb 30 inch high obstacles, cross trenches 72 inches wide or ford streams 42 inches deep. Note the exhaust right at the front coming from one of the two Cadillac V8 engines - I reckon that would have had a nice note!
The second shot, also at the proving grounds in Maryland shows the M44 on the "washboard" - a teeth shattering test to check the toughness of the machines. Engineers of the development and proof services were expert in dreaming up torture tests like this