If only you had some evidence there was a getaway car as opposed to a plain old car.
The purpose of a "getaway" car is to getaway. It is intended to Not attract attention and by extension Not attract attention to those riding inside the car. Especially if you believe the shooter(s) was/were "hired out" and had a different colored skin tone(s).
If that "getaway" car had a Texas Plate, it was either a "57" "59" "61" or a "63" Plate. Texas used White Backgrounds on their plates in those years. Just so you know, if that car is indeed a 1958, Illinois had a very similar White 1958 license plate. (Possible Chicago/Maybe Ruby connection).
This continues to be an extremely active investigation on numerous fronts.
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