[Keithc8]

You can mount the engine with rubber mounts like the factory ones or with solid ones. This just depends on the company and their engine mounts. If the engine was dynoed with the wrong balancer or flywheel you should be able to tell this when dynoed. I do not know if you could tell in a video or not. I would make sure that I had the right flywheel or flexplate because they can get boxed wrong or mixed up.
You might have a miss in the engine causing this as well. I had a guy that had an exhaust pipe against the frame and he swore his engine was out of balance till he found this problem. This is the big problem with Fords and all of their differnet styles of balancing. Good luck