NFL Connections #73, Answers
The full solution: all four groups and the 16 names, sorted from the easiest group to the trickiest.
San Francisco 49ers greats
Patrick Willis, Frank Gore, NaVorro Bowman, Justin Smith
Raiders greats
Bo Jackson, Cliff Branch, Art Shell, Gene Upshaw
Chargers greats
Philip Rivers, Kellen Winslow, Drew Brees, Keenan Allen
Los Angeles Rams greats
Eric Dickerson, Aaron Donald, Marshall Faulk, Isaac Bruce