Rocker Drain Cover and Restoration
Just in front of each rear wheel, on the inside of the inner rocker panel there are two rectangular cutouts in the rocker panel. A rubber valve is secured in the smaller opening and the flap covers the large opening.  I assume the purpose is to cover a drain for convertibles.
Not finding the part at any of the usual Firebird or GM Repro vendors or rubber trim manufacturers that remanufacture classic parts, I decided to make my own.  My car was missing the right side cover.

The flap was cut from a sheet of 1/16 rubber from Home Depot. The securing anchor was carved from a piece of scrap rubber. The two were attached with weatherstrip adhesive and painted with Krylon semi-flat black.

Flap total size:  1 7/8 x 1 3/8
Securing hole:  5/8 x 15/64
Original GM Part
New Part
New Part
Rocker Drain
Rocker  Restoration
Since making my own part, I have found a repro now available from Rick's Camaros - Part number RC-535 Rocker Drain Cover Flap
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