I recently moved into a house with an enclosed garage, and the floor had a 3
x 6 foot patch of motor oil which apparently leaked onto the floor years
ago. It is not totally hard, but more like the consistency of stiff dough.
It will scrape up if I keep at it, but it would take many hours of
back-breaking work to do this.

Any ideas how to get it up faster would be welcome.

Also how to get out the oil stain insofar as possible.