I like to do the salting method for a day or two before hand myself, adding more salt each day I do it. I also think that when you do this, it is important to let air flow underneath the meat so I put mine on a rack in a pan. The meat always comes out juicier when I do this. It never tastes salty either. I think the resting portion is also important to help keep it juicy. Injecting has always just made a mess for me, never accomplished much.
XL Big Green Egg, Weber Performer Platinum, WSM 22.5"