Best rear 1'' lowering spring????????????

[BUICK GN]

I did the 2'' front spindle and I am wanting to lower the rear 1''? Any help would be great! Thanks Matt

 

[CS99]

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[87GN_70GS]

Moog CS-5401 or NAPA 277-2045 will be about 1.1" lower, its 7.4" at 760# with a 143 #/in spring rate.
Same as Duralast RCS-5401S
About $65 thru amazon