Just an FYI, so I'm following too, there was a problem with certain makes/size of trucks and they weren't allowing them in, something about commercial size/weight etc, but apparently only at one or two AZ crossings. It was resolved last I heard.
Diesel fuel, have a few friends that go down there and diesel is easy to find, most trucks are Diesel. Quality, I'm assuming it's fine or fuel up at the border..
Here's a link to website, RVillage that has several posts/threads on it to that might help...
https://www.rvillage.com/search?query=baja&type=group&submit=
Hope that helps. You didn't say where or how far down to Mexico. Baja or the mainland..
