I've made a few trips over the years to the Golden Triangle focusing around Caborca not that far across the border. Now I admit it has been a few years since my last trip down and I would suggest making a few friends across the border before going out prospecting. There were a great deal of Canadian mining companies taking up a lot of the ground and finding who has the ground these days is a must. I had permission from one company to be on their leases unfortunately that company is gone by the wayside. Land changes hands a lot down there and looking into companies that have holding there is a great start.
Now for safety, I have no idea these days.
When I used to travel to Sinaloa to prospect with a dual citizen on their family ranch it was a blast. But the further south you go the more issues you could run into on your own. I talked to my friend earlier this year and asked him about coming down this year, his reply was "it would be better to wait a coupe of more years". Find a friend that can navigate some of the issues and if they say don't go, then don't go.
Go to Rocky Point and spend a few days and let some of the locals know what you would like to do. Vet them as well before running off into the Triangle.