Science
I remember the first car I had. it was a 1949 Dodge Coronet. I rebuilt the engine and needed to replace the ring gear on the flywheel. My dad got a cold chisel and showed me where to hit the old one. I hit it and it split and slid right off. Then he had me put the flywheel in the freezer. We put the ring gear in the oven, set at 300 degrees. Then we removed them about half an hour later and that ring gear fell over the flywheel and seated perfectly. I was amazed that it worked. I guess that is when I realized my dad was alot smarter and I wasn't so smart. My dad was a motor mechanic on PT Boats in WWII. I have used that method for several types of repairs where an interference fit is needed.