Hi,
I´m not sure if using a copy of german papers will still work. It used to, but in recent years, you always hear that the people at the TUV want a "Typengutachten" in original, not a copy. Which is not really a problem for M998 vehicles; you get them from TUV Sued (for a fee, of course). More of a problem is the "Abgasgutachten" they also demand (an emissions test certificate). Those are offered by several private test centers, but as far as I heard, the test procedure was changed at the beginning of this year, and you have to be careful not to spend money for an old test certificate.
One thing I would consider is to pay one of the german Humvee dealers and have them do the TUV procedure. They do this every week, and their TUV testers are used to test our special kind of trucks. I can really recommend Globeworks.eu from first-hand expericence, for example. You will have to adapt your Humvee to german law, which mostly means changing some of the lights, but the dealers will know what to change. Depending on the TUV they work with, some dealers have to do more changes than others. Globeworks is among those, who do very little visible changes (just the rear flashers need to be yellow instead of red, and the rear side reflectors, too).
After the TUV technical procedure, you would need to apply for the actual german title. I´m not entirely sure if you need at least a temporary residence in a german town for that.
