The United States Army contracted with R.G. LeTourneau, Inc. to build the Overland MkII. The two drawings and the image below show the primary Control Car. In the drawing shown, the Control Car has a radar mounted on the top-front and a boom jib on the rear for tire changing.
The Overland MkII is 46 feet long and 20 feet, 7 and a half inches tall with the radar. Without the radar, the Control Car is 16 feet, 9 inches tall.
In the image below, two men walk by the front passenger side tire. Note how they compare to the 10 foot tall tire and center of the rim. The Overland MkII Control Car is found at the Yuma Proving Ground Heritage Center (https://history.army.mil/museums/IMCOM/yumaProvingGround/index.html).