Hair drier and careful pulling, plus make sure the old padding has not 
swollen. 
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Use Saran or Glad Wrap to wrap the entire seat first. The covers will
slip on much easier. After you have the covers fastened in place, you
can easily remove the visable Saran Wrap with a pen-knife. This worked
great on my 56J. My brother has put about a million seat covers on
school buses, and that's how he always did it. I am thankful he shared
the idea with me. It sure made the job easier, plus the wrinkles come
out of the covers much easier.
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www.atrim.com 
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