Great info Brian. When I scaled the VW based Pink MG the percentages were nearly the same, only mine was about 200 lbs. lighter.
A stock VW is just over 2,000 lbs. so you can see the need for spring rate (torsion bar/leaves) rate reductions. In addition, a stock VW had a larger amount of front end weight, but surprisingly nearly the same rear weight.
These MGTD kits are bascially WAY lighter in the nose than a stock VW. I always believed that the driver and passenger weights in a VW kept the nose planted on the pavement anyway. So, I scaled my MGTD with and without my 260 lbs. sitting in the driver’s seat. It was nearly 20% of the weight while driving, a very important detail that should not be overlooked. Handling doesn’t count sitting still, you’ve got to be in the car.