Straightening Warped Interior Panels
The backing of the rear quarter panels is fiberboard. Same for the door panels and carpeted console side panels. I have straightened door panels for the brown 1980 by removing the upholstery, make a clamp from wood and C (or G ) clamps so that you can straighten the panel. I used epoxy resin to soak into the fiberboard then fiberglass cloth to reinforce it. Cover the epoxied area with plastic wrap (my wife wonders where the kitchen wrap disappears to) to keep the epoxy from gluing the clamped wood to the fiberboard. Clamp it straight then let the epoxy set before unclamping. You can then recover with the original or new upholstery.
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