Well, so far we're at 2 EF4s, 7 EF3s, and 22 EF2s. Note that a few of the EF2s have preliminary ratings of EF2+ and could be upgraded.
Missouri:
Bakersfield (EF3)
Des Arc (EF3+)
Poplar Bluff (EF3)
Arkansas:
Cave City (EF3)
Fifty-Six (EF3)
Larkin (EF4)
Diaz (EF4)
Alabama:
Plantersville (EF3)
Mississippi (and Louisiana?):
Kentwood-Tylertown (EF3+)
To my knowledge, the tornadoes in Gordo and Troy, Alabama have not been rated yet.
If my reading of the times on the Wiki article is correct, it looks like there was probably not a 6 hour gap at any point. We will see!
SO FAR, in terms of numbers of tornadoes in each category, the outbreak of November 17, 2013 (highlighted by the Washington, IL tornado) is pretty close. The April 15, 1998 outbreak is also similar. Interestingly, the tornado that hit Diaz, AR is, in its preliminary status, rated at about the same strength as the Washington, IL tornado.