Anyone that has ever worked on a car has probably done something that they later consider stupid - just be glad no safety issues came up because of it.
Anyway, I agree - change the rear tranny cross member support and the flex disc and it is a diyer job if you take the time. Also, take a good look around the front and rear of the engine from the top. With the flex disc being in the area where you describe these areas ain't in the same location as when it came from the factory. Look specially close at the radiator connections.