1/4 inch spacer with stock studs??

Okay I bought some 33" Mickey Thompson MTZs with some black ultra wheels. Well tried to run them and they rub my brake calipers. Decided against taking a grinder to my calipers so now I'm wanting to run a 1/4 inch spacer. I was going to order the spacer from Wheelers off-road along with theses extended thread gorilla lug nuts. What I'm wondering is will I have enough threads and also I've heard you need an acorn lug nut to hold these spacers in place. Ive had a tire fall off before which is no fun so I'm just looking for some advice on how to run these spacers properly. Preferably without changing my studs.
These are the lug nuts I've decided on:

 

Depending on what spacers you have and the length of your stock studs, you may not need to do anything. I ran some 1/4" spacers on my FJ40 for years (the kind that just slide over the lug studs) with no issues. I'm now running those spacers on my OR Trailer and have had no issues there either. Most studs have enough length to work with a 1/4" spacer. Most fasteners require a "nut" be threaded on an amount equal to the diameter of the bolt (stud). Any more than that does not really gain you any additional strength...look at the old acorn type lug nuts, most usually had quite a few threads sticking out past the nut. Then again, with alloy wheels they might not be long enough due to the thickness of the wheel...I was running my spacers with steel wheels. Wheelers should be able to tell you if the Gorilla Lug nuts will work in your application...you want to make sure that the longer lug nuts don't bottom on the spacers before they have clamped down on the wheel.....best bet is to get Wheelers OR to determine if their spacers and lugs will work safely in your application....given the choice, if the rubbing is minimal I would take a die grinder to the caliper to gain the clearance before running 1/4" spacers as most of them simply float on the studs vs the thicker machined spacers that are bolted on. As far as acorn nuts to hold the spacers in place, even 1" spacers require a special lug nut to bolt them on as there isn't enough clearance for stock lug nuts. With a 1/4" spacer, most simply slide over the lugs and are held in place by the wheel and its lug nuts.