What an ordeal!
FInally, 9 months after purchase, I have the HMV titled and registered to drive. It was a close call at the tax office. The clerk shoved a "military vehicle" form at me. As I started to fill it out, I asked if there were any restrictions..."only to and from parades and shows...". I had given her the letter on Texas letterhead, stating that HMV's can be registered as regular cars or trucks. I had to point out the second paragraph, and even then the supervisor called Austin for confirmation. Oh, they did ask for a weight slip, so luckily I had read that here on the forum and had made a trip to the local CAT Scales.
All's well that ends well. Now if it would just cool down enough to drive it. It came with AC, but the unit was just tossed in the back. I'll work on it once it cools down enough to, well, work on it.