ok I know from experience that worn out bushings tie rods etc will hide bad tires as all the slop hides the tire wobble. That being said from the tire wear, you need to do an alignment, from my experience you can do this yourself and get acceptable results. Surprised everyone is saying take it to the shop, the manual has clear instructions that will allow you to get it "pretty close" yourself on a flat surface. Worrying about caster camber before you have checked the toe in is useless. It is fairly usual for a newbie to mess up toe in when changing tie rods etc.... I don't find the 120 very fussy, has a tiny bit of toe in if I recall correctly check the book good luck.