If you do the mounts, let me know, and I can send you the instructions I followed. One thing I tried to do, but wouldn't do again, is move the crossmember as little as possible, in hopes of changing the alignment as little as possible (in case I changed my mind about the alignment). If I had to do it again, I would completely remove the cross-member, which would have made it much easier to maneuver the engine back onto the mounts. With the approach I used, it took a neighbor and I a good two hours to get things to line up well enough to allow the engine to seat properly. As I said, it was a massive pain. I'll have to check the instructions to see if I'm remembering this right, but I remember pretty clearly thinking how much easier it would have been to have the extra degree of freedom of having the cross-member completely removed.
And I agree that my clutch feel improved significantly after I replaced the master & slave cylinder, and the high pressure line. I didn't have the vibration problem you're experiencing, so I can't say whether replacing these parts would have helped with this, but it can't hurt to try. Neither the clutch M & S & line replacement, nor the engine mount replacement, are exactly trivial jobs, but I wasn't kidding when I said the clutch cylinder replacement was MUCH easier than the motor mount job. The former just requires a little patience, and moving all the lines and hoses out of the way before you start.
