Re: manual release
If your unit does not have a manual release, then crack all four fittings at the pump until they leak. NOW pull the engine up, spraying the oil everywhere.
There are pressure release valves in the cylinders and pump so the engine will kick up if it hits something. I have found that I am not strong enough to pull the engine up against these release valves. With a good floor jack, you might be able to do it. Lacking that, try three men and a boy.
Of course, if you back up real fast on the ramp with no safety chain then slam on the brakes, then rocket forward again, as you drag the lower unit through the tarmac or concrete, the engine WILL tilt. LOL (One of the shows I have seen at ramps)