Im going to put my 2 cents in, you need to decide what class you're going to run first. I'm guessing a SRT by the way the rear is moving, running FS you can be competitive, BSP, sorry no chance against a well prep'd vette or 350z. I would look into the hankook rs3, the kumho is a good tire, ive ran the XS about 4 sets BUT it is not legal in stock class anymore. crash bolts as stated are cheap and easy to install, you can buy them from mecerdes too.
I would find a set of stock size 18's and get tires, 235/40/18 and 285/35/18 or 275/35/19.. you could go 305/30/19 but it will cause the front to understeer even more.