ok i have a 1998 chevy silverado 1500 ext cab Z71. which is a better lift body or suspension and can i combine them or is that not a good idea? im wanting atleast 6" suspension and a 3" body... with eather Super Swamper Boggers or Thornbirds... which is a better tire for a daily driver and mudder and weekend?  

Body lifts have less effect on the CG of vehicle than a suspension lift but they can cause problems of their own (steering column, radiator shroud and such) You may have bigger problems though because you better plan on some new seriously deep axle gears too or better still a different truck because the drive line is not that strong and I have never heard of any one installing a 3/4 and 1 ton front IFS drive axle in a 1/2 ton and besides that you will have very short ball joint life too with that kind of lift and tires too. If you want to go wild with lift and expect it to live for a while you need to use a truck with a solid front axle and better to start with a 3/4 ton too and not just for axles and frame but also brakes because 1/2 ton brakes will struggle here. Up untill 88 GM basically used same frame on 1/2 and 3/4 tons, not so on your model.  Just so you know...  

First of all you have got a lot of questions you need to ask yourself about how you are going to use your truck and then modify it accordingly the first time and you will be much happier.  Lets here what you plan to use it for ie. street, race, pulling, daily driver, weekend warrior, etc.  Remember it is near impossible to make it awesome for every condition, but could be built to perform acceptably in all.  Another question is how long do you want it to last, are you mechanically inclined, do you have a friend that is a mechanic.  Every modification you make directly affects something else.  Sometimes it is a good idea to have 2 sets of tires. one for street and one for mud.