THE FULL MONTY By MICHAEL RIEDEL
CHICAGO — “Spamalot,” in tryouts here at the Shubert Theater, bills itself as “the musical lovingly ripped off from the motion picture ‘Monty Python and the Holy Grail.’”<br /> It might also call itself “the musical lovingly ripped off from ‘Forbidden Broadway’ and ‘The Producers.’”<br /> And when it opens on Broadway in March, we’ll be calling it “a great big lovingly ripped-off hit.”