No, didn't work on my car, but did work on my brother's car. He's had a 72 cutlass convertible in my barn for over 30 years, I told him it's time to do something about it. So we tried to bar the engine (455) over, it was seized. Not a surprise.
Popped off the valve covers, surprisingly spotless. Pulled the intake manifold, nice clean lifter valley. Then we pulled the heads and found a bit of a problem.
One of the cylinders was a mouse condo. Full of bits of carpet fragments. The piston was down at the bottom of the stroke, cylinder was completely filled up.
I pulled out a lot of compacted fluff...
Oh well, at least the heads were good. But wait...maybe not. Under all that fluff I found that a valve head had rusted off. Mouse urine sure must be corrosive. The piston top had craters in it the size of blueberries. And actually getting past a partially open valve originally and set up living quarters in the first place meant that it must have been a pretty small creature.
Not much fun going on under the hood, so we decided to poke around the back. Years ago I dragged a 12 bolt rear end out of a 1970 Cutlass to put into this car to replace the 10 bolt. Well guess what, Oldsmobile put 12 bolts on the cover, but hid a 10 bolt carrier inside. Turned out to be an exciting 2.56 gear ratio, non posi. What a drag.