Better pictures of the actual mount would help. As for height, I don't think that makes any difference..I mounted them both low and high. The frame looks stout enough, I had a frame that I replaced and the vibration went from a 10, down to a 2-3. Most important is the engine mounts to the frame. I never use pads between the engine mounts and tube. I MAKE sure that the engine mounts either fit correctly or I fabricate a front mount. The only mount I have used that did not need a fabricated front mount was a Chopper. I bought the ready made offset mount and the tubes were at a perfect 75 degree angle.
The actual mount looks good, but is the engine mounted WITHOUT any gaps. If so here are a few mounting ideas.
Engine Mounting pictures by Ron-Becker - Photobucket
Then again, no matter how the engine is mounted, the engine itself might be out of balance internally.