TORQUE BOXES ?

Sounds like you’ve done a decent amount already and I’m sure your car handles great!

So XV did some chassis testing on B/E bodies awhile back. They concluded that the worst flex was actually from the firewall forward and at the lower radiator brace. Hence stuff like the lower radiator supports and inner fender stiffening that XV and USCT offer. I posted it in another torque box thread recently but here it is
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excellent info, appreciate the response!