Scion TPS on Ford rims?

Saw an xB with a set of 05-09 Mustang Bullet 17" rims on it and thought it looked nice. Especially since I can pick up a set of take offs for under $500. The bolt pattern is ours, the width I think is 8 and the center bore is around 70 with a 45 off set. From what I've read I've gotta use 225/45 17's. But, how will I get the TPS system to work? Will the old ones be taken off my old steelies and installed on the Ford's rims? I've never seen a TPS valve or even know what it looks like or located. Any input is appreciated. Thanks!