It would be a lot of work regardless, and probably give you more problems than it would be worth. But I like your train of thought.

Have to remember, this is a transverse set up, and those upper motor mounts, and dog bones are needed for sure.
If you cannot put up with the vibration that the POLY motor mount bushings give you, you could always go back to stock bushing, and "flip" them making the main thick part horizontal instead of vertical as it comes from the factory. It puts up better with the front to back movement these engines dish out under a load from the torque if they are horizontal.
JUST the two lower mounts, one on the front of the motor, and the one on the side of the transmission are not enough alone to handle the engines. They need some help from above.
~F~