you might as well change the engine shocks since you are down there. i have not done them yet but it seems that they are very simple to replace once yu get the engine off the mounts.
i had perhaps some of the worst vibration you can imagine in a diesel.i mean paintshaker is an understatement. my mounts were actually split in half and the engine was sitting directly on the chasis practically. i had to keep the foot on the gas pedal all the time just to keep the windows form rattling out. the second i replaced the front motot mounts the car was like new so the engine shocks were not apparently required. i cant say much about the tranny mounts but if vibration is your woe the front mounts will improve it 99%. good luck