Charles servedio on youtube has a video of a 920 head I cut up and sent to him. Video was posted 11 months ago so it's a bit down his video list on his channel. It's titled David Vizard, Unity Motorsports, Mission Impossible 318 project 4 barrel test head cut aways!
He goes into depth on porting them and also has another video of flows of another 920 with stock valves.
And he has porting/flow content of various other mopar heads posted as well. Always a good show as he is an excellent porter with years of experience.
If you need more, I can post my personal photos and rubbings of the cut up head, but I'd have to take a deep think about it to describe them so you would understand it all. It was 11 months ago and I have been consumed with other projects.