I don't know if you can see this. I use a small piece of 3/4 plywood to span the heat exchanges, and then lower it onto my dolly that is made as a mobile base for my bandsaw. You can get those pretty much at any tool store. I cut out the member across the font of the dolly so I can get my large jack in to support the engine's centerline. In order to get enough height to clear my large jack I just a couple of 4x4's to space out the plywood off the dolly. It works great since it takes the minimum amount of space to pull the engine.out.
Another trick which I really like is, once the engine is down on the dolley, lift the engire rear of the car body up and over the engine...you can pull the engine out without worrying it will hit the rear valence etc.....works like a charm!
Cheers,
Mike