firstname.lastname@example.org (for Chattanooga). Getting the tour at Puebla was much more difficult, but I had a friend at VW Canada assist me with that.
Also, I purchased insurance through AXA when I applied for my temp vehicle importation permit. It wasn't very expensive ($70?). I have since received that documentation from Mexico.
My Canadian car insurance only covered me in Canada and the US so it was a necessity.
I found mexpro.com to be very useful in my preparation of documentation for crossing the border.