My guess would be the fuel sending unit. I had a similar issue 2-3 months back where I was just driving along and the truck would die as you described. I couldn't restart it until it set for a while then it would fire up and run as normal for 20 minutes until it would die again.

My fix was a new sending unit they develop a bad fuel pump connection right where the connectors elbow into the tank. This connection would heat up and break the connection to the fuel pump. Then cool down and be good for while. Might be worth popping the cover under the rear seat and having a look see with a inspection mirror.