I have taken the assy off the shaper and had another thorough look at it, and found the cross pin: over the years it had been peined to the point it was no longer visible. I was able to tap the pin out, and therefor remove the knob and disassemble the feed pawl mechanism.unfortunately there are a few dings in mine, so I cannot see any cross pin, but I agree that it is logical for there to be one. If I knew which orientation it ran in, then it would be easier to try to locate it.
The pawl rod does pass all the way through the knurled knob and does not appear to be threaded.