I was a big fan of Jim Collins.
Thought he was an excellent ILB; and was disappointed injuries cut short his Rams' career.
That being said, I think Ken Iman deserves the top-#50 recognition.
Played for Lombardi's Packers for four seasons, backing-up future Hall of Fame center Jim Ringo.
Iman came to the Rams in 1965 and was immediately the starter.
Played ten seasons for the Rams ... started every game ... never missed a game.
Ken Iman started at Center from 1965-1974.
Rich Saul took-over in 1975, and started through 1981.
Doug Smith took-oved in 1982 and started through 1991.
The Rams had three starting centers over a 27-year period!
When Steve Avila starts at center in about 50 days, he will be the Rams' third-center over a 3-year-period.
The Game has certainly changed A TON; and it's impossible to have long-term-stability along the O-Line. However, the type of stability and continuity the Rams enjoyed on the OL from the mid-1960s through the entire 1980s (25 years) was amazing even for that period.