No you don't have to buy the hole car.But i'm waiting to see what happens next year with the SRT6 market wise, I think it's already dead and the dealers will be dropping below the invoice to get them off the lot.I'm also predicting D.C. will put the new 3.5 in the XF soon 06 because of slow sales on the Crossfire Ltd.05s.Today I was offered a SRT at invoice.my choice cpe or convert.!