You have picked a conductor, a work and a recording that, for many different reasons have become somewhat legendary for all kinds of reasons, musical as well as otherwise.
Kleiber's 70s performances at Bayreuth of 'Tristan' having already become the stuff of legend for all the right reasons for those privileged to have attended and experienced them, the subsequent announcement of 'The Dresden' recording you have picked out caused much excitement and, eventually, its allotted share of controversy of several kinds that all truly great performances seem to have to garner in their wake. In fact, but for the tremendous foresight of producers during the entire recording process, leaving tapes running during rehearsals in particular, this recording may never have been properly completed at all.
It's a long and colourful story and probably best obtained from the horse's mouth at DGG themselves (click the 'read full article' link when you reach the page), which you will find here:
http://www.deutschegrammophon.com/artist/biography?ART_ID=KLECA
Kleiber's Tristans are among the most enduring masterpieces of Wagner performance we've ever been allowed to experience, unique in every respect, and governed by a man of exceptional insight and even more obsessional drive for perfection as he saw it.
All we can really do is be eternally grateful for this in every imaginable way... :-)
Warmly, as always,
Edit:
Yes, dear Alberich, I do have the 'Dresden' complete ever since it came out. Having witnessed the 1976 Tristan at Bayreuth, I too was an enthralled mutt in the queue for the 1982 recordings.
However, nowadays you can actually get to hear what we heard in 1974-1976, for they were released between 1992 and 2007 as live 'documentary' recordings which you can find here -- just keep scrolling down until you get to the relevant dates ('74-'76):
http://www.thrsw.com/ckdisc/wagner_richard_1813_1883_/tristan_und_isolde_complete/