2006 CLK 350 Cabrio Suspension
 

Newbie here on a car new to me. I'm the second owner. Have all the repair receipts from new. Front left tire wearing out on the inside corner - cords are showing so it's gotta get replaced asap. If it is alignment wouldn't both left and right be worn in the same way? Right side is fine. I expect to do the alignment first to see if that is bad and can be aligned properly. If not, then what's next? I suspect a bad strut, but FCP Euro says I need to know if it is a sport suspension to order the parts, yes? How can I determine if it is the sport suspension? If I replace one side then shouldn't I replace both sides? And springs while I'm there? 72,000 miles on the car, no front suspension parts ever have been replaced. I am I going about this the right way? Thanks in advance for your help!