I just got back from my dealer. I need two tires in the rear. The dealer told me I should get four tires as a set rather than just two. Does this ring true? Also, I am have the rear wheels adligned not to factory requirements but to have them set for straight driving, not twisties. I am a freeway driver. Makes senses???? I get to drive to San Francisco next Friday up I-5 and Sunday I will be coming home on 1. Fun - Fun - Fun!!!!