Need help deciding on engine & suspension

[el phantasmo]

Building a 72 k5. Was 4x4 converted to 2x4 using complete 85 truck crossmember. Have 250 straight six w/big erson cam, aluminum intake, hei, 390 holley carb, clifford perfermance headers. Also have 355 smallblock w/68' 302 z28 heads, weiand stealth intake, & supercomp headers. I want plenty of power, but gas prices are murder. I know the v8 can sastisfy my power requirements with the right cam & carb. The drivetrain is 350turbo tranny & 3.08 gears. Anyone running a six? I like the cool factor, but all show and no go sucks. I know this is a long post already but I have one more question. I want the truck low, at least 5/7, maybe more. How low can I go without bags and retain drivability? I know that is a suspension question but I want to hear from the blazer guys.