Yes! BIG THANKS, Will!

This draft definitely keeps the setting of the prologue during the same time period as the riots: 1974, then skips to 1977 before settling into the 80s. John Lennon even appears as himself. The names in this version are Colin Quire and Billy Connolly. The draft also answers some of the questions we've had, like
is Delahunt a cop? It suggests that Costello's fatherly feelings for Billy might have led the latter toward a new career direction and also delves into Costello's relationship with both of Billy's parents. IA's "Caesar" line is there, too.
Barrigan reveals that he was one of the other
kids at Costello's L-street garage. There's hardly anything about the FBI in the plot and Costello simply "asks" Colin
to get it over with quickly and take him out. The reasons are left unstated. And yes, there's a bit of morse code involved in the plot. Billy and Madolyn's (actually Madeleine in this draft) relationship is more tawdry in this version.
From script to screen
script...
Queenan: (to Colin) You rise fast.
Dignam: So do turds in a swimming pool.
screen...
Queenan: (to Colin) You rise fast.
Dignam: Like a 12 year-old's dick.