after reading some articles on this test what I understand that the "FITMENT" of body shell, panels also matters a lot. The way its tightened/ torque wrenched and the way a panels is aligned. minor things will make a difference in transferring the forces. So you can have same body panels and chassis but fitment of it will bring different results. By the way just image how these cars will do in side impact crashes.
NHTSA the US testing facility also give details of under carriage in test which is more detailed. Like for new corolla
For learning I am attaching a detailed report on 11th gen US Corolla, Just read how extensive and detailed this testing is . here http://www.docdroid.net/kpvh/v08407r001.pdf.html
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