No, the 55 springs are made for 55's only.
That is why aftermarket 55 springs are also made for 55's only. Yes, you can fit them, but they are not designed for any other weight. While there may be more a difference between the 320 and 430 than there is between the 430 and 55, springs react differently depending on weight, not difference in weight. I only brought this to light to protect anyone who may not be aware of this. Any CLK can put those springs on their car, but the results will not be the same. Both a 430 and especially a 320, will be higher in the front due to the lower weight placed upon the spring. This is also why Cabriolet's have different springs...