Got my Cutlass back - the mechanic shaved a few millimeters off the nub on the torque converter that fits into the crankshaft. Apparently it wouldn't fit snug with the flexplate unless he did that. Everything seems fine when the car is cold, but after it warms up and I rev the engine in park, I can hear something spinning to a stop underneath the car near the transmission after I let off the gas. It's not very loud, and I can only hear it if I have the radio off. I can just barely hear it with the windows up, and I still have to pay close attention in order to hear it when the door is open and my head is hanging down near the ground. I assume it's the torque converter, but I pray that it's nothing to worry about. He gave me a 4-month, 4000 mile warranty so hopefully it'll get itself figured out by then.