Greetings from one of the truly great American cities. I wanted to post this postcard from San Francisco sooner but I arrived Friday night and had some other work to do before the sightseeing and people greeting began.  The Packers and 49ers from Candlestick tonight will be the ultimate determination of how the weekend goes, but I wanted to delve into the history of this rivalry.  Not just the relatively recent playoff history.  This is my fourth trip since the 1995 playoffs.  The Packers won here back then, beat the Niners for their second straight NFC title the following year and of course, lost on the TO catch following the 1998 season in what turned out to be Mike Holmgren's final game.   But these franchises go back quite a bit further.  San Francisco was an original member of the old, All American Football Conference back in the 40's.   They, along with Cleveland, were welcomed into the NFL after the 1948 seaon.  Then, every single year from 1950 through 1963, the Packers boarded a train and eventually a plane, to head West for a season ending back to back West Coast trip against the 49ers and the Los Angeles Rams.  They went 5-9 against Fricsco in that time, remember, the Packers in the 50's had their struggles.  The games were played at Kezar Stadium, a relic if there ever was one.  The playing surface was encircled by a track and there was a huge, arched monument well behind the west end zone, classic.  Last night, I headed to Kezar to check it out.  The big granstands are long gone but the stadium remains intact and even in use.  Across Stanyan street from the stadium is the Kezar Pub, so why not?  Once there, I met some 49er fans anxious for the ballgame, one young man in particular.  Cory Ross told me he attended Butte Community College a couple of years after Aaron Rodgers left and closely followed his career at Cal and then, Green Bay.  He even made the pilgrimage to Lambeau in 2010 to see Rodgers against his Niners.  Adorning the walls of the pub were big photos of the old Niners,  Y.A.Tittle, Hugh McIlhenny, Joe Perry.  It was a fascinating flashback.  Even dimly lit still at night, you could hear the Kezar roars.  Movie buffs may remember the place, it's where Clint Eastwood first tracked down the "punk" in Dirty Harry. Let's hope the Packers "feel lucky" tonight,