They did mention 3D scans. And they have some NOS panels too for scanning and reference. They are the only ones I have seen make the inner rocker and the lower a pillar. As well as full floor pans They test fit their products too.
Z32 doesn’t use struts either. For the rear I guess you can do the same as the 510 guys? I don’t trust it. I agree with datzenmike or maybe upgrades that are within reason. Like not reinventing the wheel.