| Usually they say not to stagger all wheel drive vehicles. I would check as it has something to do with the way the car tracks and the power appropriated between front and rear. Not sure, just what I heard also.
If the wheels came off of the CLK, just check the offset. If its at all close to the standard of the E, you will be fine. But test fit before buying tires. Thats really the only way to tell. I am assuming by hubs, you meant spacers. | 
