I have already stated that the wheelbases are different back on page 1. That was never disputed.Here is a tub on top of a long flat chassis, nose plate screw holes aligned, dimensions are the same from there forward. As you can see the flat chassis is clearly longer on the back. NDS chassis also pictured for reference.
And no, the dimensions are NOT the same from the steering pivot holes forward; The second step of the kick-up on the black tub and RTR chassis accounts for another 1/4" in TOTAL length, making them 14".
With pivot screw holes aligned:

Simply put, neither chassis will fit in a box of less than 14" without bending.