K7030 is the cam bolt and bushing package, Moog claims the cam bolt allows "Plus Or Minus 2-1/4 Degree Camber And/Or Caster" vie the other offering that allow 1 degree. K8243A is the Moog number for just the cam bolt,

I think someone with both types and a dial caliper would have to measure things out and see what, if anything, is the difference. The pics on RockAuto really don't show a difference.