Definitely mark the ones to be cut and double check before cutting, I made that mistake.

I ended up cutting every other tread off and didn't personally like it to much, pretty unstable setup. What I did next is cut every tread off on all tires for a "slick" effect and was much more pleased (although those sucked also to be honest, the compound just isn't right on stock maxx tires)

I used lexan scissors to cut off the treads, works pretty good.