I love my solid mounts from Car Quest. They were the cheapest in my town, and are good quality. I paid 149.50 for both, with taxes. (Canadian) There does not seem to be any more any vibration with these over the stock fluid filled jobs, which will never hold up my 3.8 S/C again. What a silly idea those were!
NOTE: You need to reuse your original brackets, you only get the rubber insert.
Part #31-3503
ALSO: Take it to a very competent S/C mechanic. This job is not for the faint of heart, or ill tempered. If you go to a good mechanic, it will cost you less in labour if you know what you are doing.
TIPS: Loosen the windshield lower cowls, as you will need to jack the motor up quite a bit. Use a 2X4 wood on your jack and lift on the oil pan so you don't damage it.
Be careful on the pass side. There is a two piece knock sensor screwed into the block, with a heat shield on it. You can remove the sensor using a deep socket, while leaving the insert in the block as not to loose all of your coolant. The sheild can be bent up and out of the way to make room, then bend it back afterwards. The knock sensor goes back in dry. Do not put any sealant ot locktite on it.
Drivers side: Mark the steering shaft rag joint for realignment, then take it apart, it will slide up into the firewall quite a distance. This gets you a fair bit of room on the drivers side.