I have 3/8 spacers right now and it's worked for years if I use the 1/2 my lug nut would be flush with the stud when tightened I'm assuming that should be good enough... I never fully lock out unless maybe I'm turning around or something I just don't wanta ruin the new tires lol.. I went up a size smh.. how long you gonna be there for? I will be in glamis on Tuesday for vets