Weird Vibration!

should be able to do this while it is in the car. I don't see why I can't.
Absolutely no way can you do this in car unless you have removable floor pans. As said most of trans has to come apart. Housing will NOT come off by just removing the bolts! Much too much info to list here, you need a service manual or at least a Chilton or similar book. If you get truly desperate can scan some pages.