Thx for sharing Steve.
In my view, US brochures should be divided into two separate categories.
1) General 02 brochures which were translated into different languages - among them American - and distributed all around the globe.
2) US-specific 02 brochures, which were only distributed in the US, and differ from 02 brochures seen elsewhere in the world.
In my experience, the easiest telltale is the number plates. If the 02's are wearing German numberplates, then it's a general brochure which has been printed in a wide variety of languages. If however the 02's are wearing a US numberplate, then it's a US-only brochure, and as such the pictured cars will usually also feature all those US-specific details.
However there is of course always an exception to every rule, and I believe your first brochure here - the BMW 1600 brochure from III/68 is indeed a US-specific brochure despite the German numberplates. I have never seen a copy of this brochure in Europe.
Your second and fourth brochures - dated IV/68 and VIII/68 - are general 02 brochures, as these were available in Europe too. I too believe that your IV/68 brochure is the first 2002 brochure - I have never seen an earlier one, though bizarrely my own copy of that very same brochure is dated III/68. The fact that the 1600ti is included in your VIII/68 brochure is a dead giveaway that it's a European brochure which somehow made its way to your shores.
Your third brochure - BMW 1600 / BMW 2002 brochure dated V/68 - is the earliest brochure I have seen thus fare to feature pictures of 02's wearing US numberplates. It is clearly a US-specific brochure. It is annoyingly also a brochure which I lack in my collection! The earliest US-specific 02 brochure I have is a 14-page BMW 1600 / BMW 2002 brochure with a Granada red 02 on the cover, and it's dated X/68.
Of course, as we got further into 02 production, it gets easier and easier to recognise the US-specific brochures, as there were more and more differences between Euro and US cars. It all started fairly subtle with slightly larger overriders, and the two-piece dash being introduced 3 years earlier in the US compared to Europe. But by the time the SRL 02's came along, those massive federal bumpers where a rather in-your-face difference, which probably also made the need for US-specific brochures more apparent.
Of my 28 different 02 brochures, only five of them are US-specific. The earliest I have already mentioned being dated X/68. The next bizarrely doesn't have a date on it, but various details make me believe it would be from '70. The last three I have are all from the SRL era, being dated 2/74, 1/75 and then 2/75 (despite the last one clearly stating "1976" on the cover).
How many other US-specific 02 brochures were there? Surely there must have been some on the second series of 02's from between 04.71 and 08.73...??