rear corner trim

The rear corner trim has, as shown above, the generic part # of 278D12 for the right-hand one, or 278D13 for the left-hand one.  But, you need the prefix and the suffix, which gives the color, to find a replacement.  Unfortunately, according to Numberdummy in this thread on FTE, those panels were obsolete by the time Ford revised the master parts catalog in 1994 so they removed it from the catalog.  However, he has an earlier copy and has these part #'s in case you can find one:

• E3TZ-10278D12-A9U Right & E3TZ-10278D13-A9U Left .. Tan
  
• E4TZ-10278D12-A8P Right & E4TZ-10278D13-A8P Left .. Charcoal
  
• E4TZ-10278D12-B3D Right & E4TZ-10278D13-B3D Left .. Red
  
• E5TZ-10278D12-B9B Right & E5TZ-10278D13-B9B Left .. Blue