Possible Clues:

• Name of eighteen undisputed kings of France
• Ring great Joe
• Armstrong who signed letters 'Red beans and ricely yours'
• With 46-Down, “Jump, Jive an’ Wail” singer
• Name of French kings
• American world heavyweight boxing champion for 12 years, d. 1981
• The L in 21-Across
• St. ___, Missouri
• The L in 27-Across
• NFL analyst Riddick