So back in the late 90s I worked in radio in Hartford, CT and sold a carload of my station's old reel to reel master tapes that I had transferred to DAT to a tape collector in Washington, DC. Guy had a ridiculous reel to reel setup and was a bigtime collector, he spent 3 grand on the tapes I sold him. During our meeting to exchange the tapes he started asking me if I knew anything about Zeppelin and live recordings (it was, unknown to him, my specialty). He was more a of Dead guy, where basically all of their shows were recorded and available for trade. He told me of a fellow named "Arizona Bob" (or something like that, my memory isn't the best) who had worked on Zeppelin's crew and had recorded all of the 1975 and 1977 shows to reel. He was looking to sell the collection to one buyer and was asking somewhere north of 25k for it. He asked if I thought it was a good deal. I nearly shit my pants and told him that those shows did not exist - nothing was available besides the Dallas show at that point, which was incomplete also. He said he had recieved some snippets of the shows and they were in fact real. I said without a doubt he should buy them. Months later I contacted the guy and he told me someone had outbid him, and that was the last I heard of it. Then a few years later all the '75 and '77 boards start showing up... So they are out there.