Just to make sure we are all on the same page... Did you remove the flywheel shroud and flywheel to gain access to points? I don't see the flywheel or shroud in any of your pictures. I'm not trying to insult anyone's intelligence but when you indicated it has a tapered shaft on one side and straight shaft on the other, it leads me to believe you potentially don't realize that the flywheel and the shroud / starter assembly are missing. Again, my apologies if you are aware of this and just left them out of your pics.
If you do have the shroud, can you post a couple pics of it? (3, showing the top and both sides if it's not too much trouble!)
Finally, from the pics, it doesn't appear that any of the 8 head bolts are snapped off unless perhaps you tried removing them, they snapped, and you left the top of the bolt in place. (or perhaps you tried getting them out after you photographed the engine!) If indeed some did snap off, I've had a lot of success using left hand twist drill bits. The key is center punching the stud to start with. BTW, Harbor Freight sells an inexpensive set that I've used several times.
For what it's worth...
