An Orion Home Video trailer for the movie over at You Tube, titled "State Of Grace 1990 Movie", features shots from a few deleted scenes. One of the actors in these clips, given a couple close-ups (at 0:37 and 0:39, respectively) and a line or two appears to be Michael Gambon, playing, I assume, Flynn, the mob boss Ed Harris had hit so he could take control of the gang.
I'm only guessing here, as I haven't been able to locate any info indicating Gambon was involved in the production, but it sure looks and sounds like him.
UPDATE: Just had my suspicion confirmed by Phil Joanou's audio commentary on the Twilight Time Blu-ray. Gambon's scenes, as the Irish mob boss Ed Harris bumps off to take control of the gang, were originally set to open the film, but re-shoots were done to more firmly establish the story as being about Sean Penn's character, leaving no room for the Gambon scenes, which, by then, were considered unnecessary to the plot.
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