Interesting, all. When I was young working on heavy eqpt, I was helping to assy a large excavator. I drove a tight pin in the main arm, and it gauled and stuck...had to cut it out with what was called an air arc, now goes by a different name. On submarines, the main shaft is fit with no keys, and a taper press fit. And, when I have had issues, heat has always been a friend....not too much. Some cases you warm a thin walled cylinder liner before pressing in. In others, the bolt has to be red before it will come loose. And, on an aluminum harley engine, a friend found that when a steel bolt or stud breaks off flush, you tig weld a nut on top, and the heat will loosen him, and the nut will remove him. Never sure what is right, as seen above. But, since I am a poor retiree and trying not to get the large press kit for one job.....I am working on a homemade job that I hope will get er dun. But, I always like the other points and the help, thanks.