There were at least a couple of articles about this at mbz.org. Never done it myself, but iirc a piece or coathanger wire or whatever you can find of the approximate right diameter to hold things in place is correct. Knurl the gear end of the shaft w/ pliers or whatever, jbweld, superglue, flavor of the month, whatever floats your boat. Reassemble. You might find the articles cached somewhere if you look. First time I had this done it lasted a couple of yrs. Second time the indy I was using said he was pretty aggressive with the pliers; been working since, maybe 8 yrs or more.
joe