For '07's the 17x8's would have a 5.72" backspace, the 17x9's should have 5.94". Not a bad price at all with the tires.
As far as whether or not they'll fit, if you're running an A body rear you'll need spacers. 1", 1.25", and even 1.5" spacers are available, so you can make them work. If you have a B body rear you'd be in better shape, they'd be real close to bolting right on. Those are 27" tall tires though, so you'd probably want to go with shorter tires in the front.
