05 z71 5.3 sierra. I already have 20" wheels that I would like to use, i beieve 8.5 wide. I want to do a lift and put 35's on the wheels. The dealer in my town can get me BDS and fabtech 6 inch suspension kits. any opinions on either of these two kits? what about 3inch body? I am completly new to lifts and pretty much anything to do with suspension so all the help i can get would be great. will i need to do different gears with this set up?