70 Nova Front Coil Spring Question

[Gbg7849]

All, I am new to this site but thought that someone here might be able to help me.

I am trying to clone the Yenko Duece stance on my 71 nova. I like the classic Yenko stance that is squatted in the rear and raised slightly in the front. I believe I have all the components except for a question on the front springs. It is my understanding that all the F41 suspension utilized the Heavy Duty Suspension springs GM 3955727 Code HH (base), or HJ (295 and over extra pounds); Spring Rate 400 Pounds per Inch.

I am not sure which spring is the right one. Also does anyone know where you can buy these? Thank you for any assistance you can give!