Interesting question since those copying the originals are doing a great job but are not acknowleging they are copies... One way is to look at the staples that hold the pages; my original '72-1/2 red owners manual is 40 years old and the uncoated Italian staples have rust-stained the pages where they touch. This may not work on the earlies- the repro blue manual I have is edge-bound.
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