I recently came across this the other day, and had a field day. It's quite literally a goldmine of lost content regarding the troubled editing process with this Stallone/Cosmatos classic. While not everything that was sadly cut from the first Workprint version, there's still a ton of stuff in here that kind of blows my mind, things that I had never seen before or was even aware of. While we may never find that lost and mythical Workprint of this insanely badass classic, this will have to do.
Special thanks to YouTube user Jack Craven for putting all of this together from various sources.