No the dash was changed the bulkhead might have a hole here and there but the overall size and dimensions of the bulkhead stayed the same
Still doesn't explain why the bulkhead is critical to crash tests.
And FFS, it's just a piece of mild steel welded in a jig. It's not rocket science.
Changing the bulkhead, assuming the basic mount points and general profile for the front wings and doors are retained, wouldn't affect the production line much at all. Considering that the thing is built by hand, it would take a few days training to get the factory fitter's heads around the new process.
Your missing the point - the Defender has NO forward crumple zones.
The firewall is considered the safety barrier - as legislated at the time and is certified to that standard.
To change that component requires complete recertification.
But they did try something's :-)
I knew a bloke who worked at one of the biggest airbag manufactures in the Uk and he told me in the 90's Land Rover talked them with putting an airbag ina. Defender. They were all up for it until Land Rover Handed them the steering wheel and then they laughed and handed it back. Land Rover weren't willing to change anything around the steering wheel they wanted them to just fit an airbag into the existing steering wheel. End of test.