Excellent point, and one worth mentioning, to be sure. It never ceases to amaze me just how differently the same regulation can be interpreted or enforced based on where you are or who is in charge! This goes for many things down there, not just vehicle stuff.
It's important to note that Baja and Sonora each have different criteria than the rest of Mexico. In an effort to bolster trade and tourism, or for whatever reason, they have trimmed-down standards there as long as you promise to stay in those states only. I am not familiar with those areas at all. Thanks for filling in those gaps!
For most travelers, though, the regs posted in the link are the whole kit and caboodle, straight from the to-do list provided at the aduana. Regardless of what's actually asked by you at any given border, I'd still recommend being fully prepared to cover every base. For example, I have heard of many people who failed to turn in their temporary vehicle registration, only to be denied access to Mexico the next time they tried to enter. At that point, the govt of Mexico thinks you simply sold the vehicle illegally within their country during your previous trip. Bad juju, as now you have to prove you didn't.
Very common, this one, and actually met a guy who was dealing with this just a few weeks ago. I think I literally watched his hair turn gray. Not a fun way to spend a day when you're trying to get to the beach.
If you're not asked to surrender your tourist permit or vehicle tags upon your return to the US, I'd recommend calling the local Consulate's office when you get back home. Let them know what happened and they can get you and/or your truck removed from the country officially. It's important if you ever want to go back, and critical if you want your $200-400 deposit back.
Off to update my article with this added info. Thanks again for helping think of the other facets to the story!
wc