I'm potentially on the search for a SLK (R171), specifically the 350 model. I've a few questions: - Was there a facelift/engine upgrade in 2008. As 2008 cars are listed as 305bhp, whereas earlier ones 272bhp, or is this an Autotrader typo? - Are the exhaust tips on all SLK350 >2008 cars rectangular? - Is there a rear panel (diffuser) missing in this car? Many thanks.