http://www.youtube.com/watch?v=x75Pywf723s someone hand cranking a FW - not very efficient though
http://www.treadleon.net/sewingmachi...k/fwcrank.html
I think what they did with the wheel would work for any hand wheel.
You need not only the motor mount boss but it has to line up with the center of the wheel.
My 319 has the boss but it is not lined up straight with the center of the hand wheel so it will not hand crank.
I have a Singer 66 redeye I hoped to HC - no motor boss - it merely has a tapped hole to hold a motor. The shaped part is not there and it goes at an angle rather than straight up and down - so that won't hold a HC.
here is another type of HC only one revolution per crank though.
http://www.ebay.com/itm/FEATHERWEIGH...46235745492338