You should read the book. There's some elements of it remaining in the film but David Peace's writing style is impressively 'different' and well worth reading.
I believe Michael Sheen was the actor playing Cloughie, although doubtless Martin would have done a similarly excellent job, with Brando playing Revie presumably.
Michael Sheen is a proper British character actor, something the Hollywood system cannot produce. He was equally convincing as Brian Clough, Tony Blair and Kenneth Williams - three very different faces and voices - particularly when his normal speaking voice is quite a strong South Welsh accent.