Don't throw away those panels just because the backing boards are broken and warped! You cannot buy reproduction panels for the 67-70 Mercury Cougar, but you can get this pair of backer boards. If your vinyl is good, then you will want to put the work into them. These are not a quick fix, they do take time to install but the end result is worth it. These will work on your 67-68 XR7, Decor or Standard model as they are cut for all models and all options (i.e. manual remote mirror, courtesy lights).
Now precisely CNC machined with the proper perforated "punch outs" like the factory panels. Made from a much more durable hard board, these should last a lifetime without warping.
*Keep in mind that we no longer have anyone working on our door panels at this time (as previously stated in this video).