[mdross1]

Nothing more frustrating than squeaks and rattles. Aside from tearing the car all apart and putting it back together,finding the causes are a pain. It would be easier to have someone ride with you and focus on where the noises are coming from. Spend some time walking around the car use the butt of your hand see if you can recreate these noises. Open the hood and trunk lid do the same thing even with the car on a lift eventually you will find the sources of your frustration.
Keep in mind these cars ride stiff because of what they are and were never meant to be luxo cruisers.