I'm looking for an economical leveling kit for my '06 Colorado Z71, I5, reg cab. I do not do any off road driving and am only looking to give my truck a more aggressive profile and appearance. Has anyone had experience with Suspension Specialists 3+3 torsion key, shackle, procomp shock kit? With only road driving, is an upper bj flip necessary? I am planning a differential drop. I'm 60+ years old and not afraid to dirty my hands but don't have air tools. Should I have a local shop install and how much time would it take for that work? Thanks for your advice in advance! I tried to do a search on this but my shit android tablet won't let me type in the search words.