for tire size....you will need to run a 215/35/18. other wise its going to be not only too tall...its going to rub.
and like mentioned.....the most important piece of information is missing...what is the offset of the wheels you are looking at...
for the MP3....if that wheel is 7 inches wide you will need a +43 mm offset....if its a 7 1/2 inch wide wheel...you will need a +45 mm offset....otherwise you will rub.