Anyone know the history of the project or script???

The screenplay is credited to 3 different writers with 3 very different sensibilities. Two of them were also directors themselves whose directorial careers were in decline or effectively over by 1990. I can't imagine the 3 of them in a room together churning out pages to fax (messenger?) to Clint's office.

It's possible that Kennedy & Bridges each planned to film the Viertel novel well before Eastwood finally did it but, if so, when? Did any of them work directly with Eastwood? Or is there another story altogether? I'd appreciate any insights.