Shimming Engine for Header Clearance

I would think that if you leave the passenger's mount in it's original position and put a shim "under" the Driver's mount all you're going to do is raise the driver's side of the engine. It would take a tremendous force to move the engine over (sideways) 1/8" of an inch without relocating the passenger's mount??? Seems to me like you'd be trying to push the engine over to the passenger's side but the passenger's mount will not let the engine move very much at all. However, it will raise the engine on the driver's side.

treblig