Well, the new tires will be .8" wider overall, so they would stick in about .4" further than the current tires. I'm guessing you could put those on without the spacers, but I could be wrong. If not, the spacers should bring it out far enough.
Also, those tires you want to switch to will be about 2" shorter.
Try this..that way you can convert the tire size into inches
Tire Calculator
