Excellent mapping of the da qiang drills to open hand work
Solid training - Dou Qiang at 8:17 or so rarely seen on Youtube and one of the major exercises - you can also do one arm thrusts when done correctly really shows chan si jin workings.
https://www.youtube.com/watch?v=qkZeCZstRlI
Masters of Taiwan ep6 Classical Long Fist and Spear with Han Ji Xiang