alignment caster camber bushings... cogged or hex head?

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does it matter what bushing is used? alignment shop says cogged are for 3/4ton trucks not 1ton straight axle and i need to install hex heads. parts store says the cogged (Raybestos 611-1127) is the right part for my truck. i see results for both styles when i search napa for bushings that fit my truck. do i need to pull these and find hex?

 

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the hex head is for the crew cab.