examine the rear subframe mounts. The front mounts will show excessive movement when you pry between the body and rear subframe at the lower front mounting points. Also check the thrust arms. Those are the rear links that are about a 45 degree angle to the rear axles. To check for play grab the link with the biggest channel locks you can find and move it to examine for excessive movement. If you check without some sort of lever you wont find any play.

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1990 190E 2.6
1996 Grand Voyager 3.3
1985 Mustang GT 5.0 5 SPD
1982 Suzuki GS 750T