SLK/R170: will these wheels work?

i was gona put the 18x8.5 in the front and the 18x9.0 in the rear. For some reason i can't find any info on back spacing and the say these are for the CL and S class. can i put these on an SLK or do i need to get the 18x7.5 front and rear AMG dual spoke like this?

getting wheels ordered tomarow. thanks


