Changing crankshaft bearings with the engine in the car.
I have done it, but I am too old to want to lay on my back that long anymore. My buddy’s 71 Demon has a 360 with a deep oil pan, that he could barely get out of his driveway. He debated on changing the oil pan with the engine in the car, I had him drive it to my garage and pulled the engine, swapped the pickup and pan and had it back together. I felt that it was easier for me.