I tackled this problem with my SR Litage frame. Tried all the suggested methods along with a liberal amount of cussing and thoughts of sacrificing a virgin or chicken.
By happenstance, I had the cable stuck down the tube when I started twirling it back and forth between my finger and thumb. To my surprise, it popped out the back end. Tempting fate, I pulled it back out and repeated the process. After several successful repeats, I can only surmise that there is some type of ramp or funnel installed that helps thread the cable through.
This is Africa, 1943. War spits out its violence overhead and the sandy graveyard swallows it up. Her name is King Nine, B-25, medium bomber, Twelfth Air Force. On a hot, still morning she took off from Tunisia to bomb the southern tip of Italy. An errant piece of flak tore a hole in a wing tank and, like a wounded bird, this is where she landed, not to return on this day, or any other day.