arXiv submission with PDF and data, preferred submission strategy?
I see a fourth way forward. You could upload the database to a separate repository and cite that in the paper. (E.g. Zenodo allows multiple files, but putting them in an archive file might be beneficial.) Then submit the PDF version of the paper to arXiv.


  1) put the paper describing the database into tex format without their letterhead, or reducing it to an image. Be done. Incur an unknown level of coauthor confusion and wrath (they are oddly worked up about this). I would value easy (converters that work?) solutions in this vein.


Well, don't do that unless you can get your coauthors onboard. If you can convince them, you can try Word -> TeX converters. Some possiblities can be found here. The letterhead might have to be handled separately, possibly as graphics that you then auto-vectorize in Inkscape or similar tools.


  2) Have two arXiv submissions: a) the pdf of the paper b) the csv data dictionaries (2) and json databases (2). Reference b in a.


I don't think arXiv allows a separate submission for only the data. Hence suggestion #4 above.


  3) Write the arXiv folks asking for an exception. I'm not sure they do this.


I have never heard of them making an exception, but I have also not heard about anyone asking for one. However, even if exceptions could be made, that rarely translate to "a quick process".