Peter, I have some of the 'ZF manual' written in German, but not all the usual pages are present. There were several 'manuals'- for a dash-zero (GT-40), dash-1 (Mangusta) and dash-2 (Pantera). Not all of them are the same- parts vary, including castings and sequence of the work needed. For overhaul, even the best of them are only 40 pgs (in english) with photos that don't show critical operations, missing views on how one uses the factory tools for setting up, and so forth. This is from an actual printed-in-Germany (in english) factory manual. Available reprints are far worse.
It probably won't help you much, but one owner said that he found working on his ZF was very similar to overhauling a Ford top-loader 4-speed transmission from late '60s Mustangs.
Sent me your real e-mail address so as to not waste George's bandwidth on the Forums, and I'll compile what I have as pdf files. Just don't expect to read the manuals and then tear a ZF apart & reassemble it competently.
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