[obijuan]

I fit 37s on my 4 inch springs. I dont think thats what youre looking for. 2.5" might be more what you have in mind.

73-87/91 square body trucks all share the same front springs. 1/2 ton rears are 52" long where 3/4 ton and 1 ton are 56" with varying capacities.

If the lift kit you found is blocks in the rear then they will fit your k30. Just ubolts are the only change.