[gerfunken]

I've got a 72 k20 as well. I went with a superlift 6" lift, and am running 35's. I opted not to go with blocks in the rear, and have replacement springs. Also the shackle swap wasn't an option, as I've seen that it changes the rear suspension (can't remember the site that I saw that on.)

I think that I spent about 1200 on the suspension system, including shocks and a new steering arm.