You should be able to reuse the pressure sensors but this entails breaking down your 18" wheels and tires.

I got my 239s from Ameritrades who is in CT. He often sells wheel/tire sets on ebay. Mine were perfect.

You should consider the fender flares as well. The 325s stick out a fair amount in the back without them.

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2012 F10 550xi Carbon black/oyster
2011 E92 M3 SSII/black
2012 W166 ML63 Steel grey/porcelain
2007 E93 monaco blue/beige (retired)
2010 E70 35d Space grey/saddle brown (retired)