Dealing with almost the EXACT same thing myself. Last thing left to do is to replace the transmission mounts. The old stuff gets weak, collapses and/or separates from the metal plates. It may look totally normal when up in the air, but when they collapse it changes the front driveshaft alignment angle and causes a vibration, if left unchecked it will wear and tear the rubber out of the center support bearing. So its a fairly cheap and easy fix to replace the mounts, its the two small bits holding the tail of the transmission up on the crossmember.