The model kit is a pretty good representation of the first pilot model, the T55.
The second pilot model, the T55E1, featured a major rearrangement of components
and an angular hull in place of the curved plates of the original design.
The two Cook Interceptors are briefly covered on pages 163 to 165 of
Armored Car: A History of American Wheeled Combat Vehicles by
R. P. Hunnicutt, 2002 Presidio Press