Restoration help

Hello everyone, I thought this would be the best place to come to for honest advice.I recently purchased my second 928, it's 91 gt. It's in good condition but it's got a few gremlins. There is a vibration, even at low speeds. If I simply race the engine while in neutral I still feel it.
What I'm hoping is to find a shop that can basically restore the mechanical end, I have someone to take care of the paint and body work. The interior is very good with the exception of the drivers seat, some of the pleats are separating. I plan on shipping the seat to 9leather for repair.
If anyone has a strong recommendation for a top notch shop please let me know.

The vibration could be due to collapsed original engine mounts. An easy diagnostic tip is to raise the hood and stand at the front of the car while a helper races the engine while you observe the engine and chassis. The engine should noticeably shake from the increased RPM. If it isn't, then the mounts aren't absorbing the energy anymore. The body of the car is.

As far as recommending a shop.. Where are you located?