Whats the real world difference between the two springs below? Ride height, firmness?

Mopar Performance Competition Leaf Springs P3412002 3200 lbs
Mopar Performance Competition Leaf Springs P4120863 2800 ibs

33 Plymouth Roadster - 383 - 5.90 1/8th 9.58 1/4
68 Dart - 340
66 Belvedere - 400

Windy Hollow Garage - https://www.youtube.com/@windyhollowgarage