There are several variations of the worms, pins, washers, and sprocket and rim drives that all need to match for everything to work right. Been there, done that. This is across the board for the 1111 series saws from the 050 to the 076 and can become a nightmare to sort out especially if you only have some of the parts to begin with. On the other hand, I'd say your bigger problem may be the threads on that crank.
Here's a vid I did a while back on the general subject of the 1111 oil pump drive variations and how the different pieces do and don't work together. A little..., (ok, a lot) long winded but covers most of what you're up against. Wish I would have had a wider angle, but you should get the idea. Hope it helps.
I also have quite a bit of 1111 documentation if you run into anything else that may need clarification. There's also an extensive thread on the 050, 051, 075, 076 on another forum the covers just about anything else you may run into.