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With the trim installed, take the piece of drywall that was originally cut out. Gently slide it back up into the opening in the ceiling, allowing it to rest on top of the newly installed wooden trim. This piece now functions as the removable attic access door. The trim may have been pre-primed, but to achieve a fully finished look, apply caulk to fill in any cracks, gaps, or nail holes between the trim and the ceiling. Smooth out the caulk for a seamless finish. Once the caulk is dry, the trim can be painted to match the ceiling or a contrasting color, if desired. The attic access is now complete and ready for insulation contractors to utilize for blowing in new insulation.