Well, we've done some Btype (our cars) vs Dtype (the new one) photo back-to-back checks and it seems that some pretty major work has gone on underneath the car (The Aussies really have something to look forward to!!
Apart from the fore-mentioned re-inforcing, looks like bushes, some location points (dampers being one) and links have been heavily revised
, which would explain why the car is so much better! (just for flameproofing - IMHO)
Gotta find a manual to test!