You really shouldn't go more than about an inch lift on the factory A-arms and lifting won't keep the tires from rubbing all the time anyway since they will still rub under compression. The trimming you need to do is extremely minimal and only to the plastic piece behind the wheel. Just take a dremel or clippers or something and cut a little bit out right at the bottom behind the tire. If you turn the wheels you will be able to see where and how much. It's very minor and nobody will even notice it. Those plastic pieces are only about $20 anyway, so if you want to put it back to stock later it's no big deal, although i can't imagine anyone bothering.