I would like to add to the kudos already given to Mofi for his advise. I think he steered the OP in the right direction given the age of the speakers and other considerations. Having said that, as someone who loves those speakers and who came very close to buying a pair of original CLS's when they were current I would like to add some thoughts to the mix of great info here.
I listened to the original CLS's at length and several times at local dealers (Sound By Singer mostly) and one aquaintance before deciding to go in a different direction (Maggies). For whatever it may be worth I remember clearly that the original CLS was generally considered by reviewers and at least a couple of CLS owners I knew to be "the one" with the magic and that the changes to the speaker up until the introduction of the 2Z to be improvements in amp friendliness and tonal friendliness by being less ruthlessly revealing, but also being somewhat of a step backwards in some ways. The 2Z seemed to strike the best balance between all those considerations. Fantastic speakers!
I listened to the original CLS's at length and several times at local dealers (Sound By Singer mostly) and one aquaintance before deciding to go in a different direction (Maggies). For whatever it may be worth I remember clearly that the original CLS was generally considered by reviewers and at least a couple of CLS owners I knew to be "the one" with the magic and that the changes to the speaker up until the introduction of the 2Z to be improvements in amp friendliness and tonal friendliness by being less ruthlessly revealing, but also being somewhat of a step backwards in some ways. The 2Z seemed to strike the best balance between all those considerations. Fantastic speakers!