70 Camaro Speedtech Torque arm. Which shocks/springs?

[tbal]

Little bit of a dilemma ordering shocks and springs for this new setup.

My old ridetech 4link setup had 2.5”ID 12” springs with 185 lb spring rate and seemed pretty damn stiff then and now even installed these on the speedtech setup.



Now speedtech is recommending;

QA1 DD417 shock. 5/8 bearing 1.25 width and a 10 inch 300 lb spring

strange recommended this setup https://www.strangeengineering.net/p...4-stroke.html/

i am confused on what to do.