I believe the # 4-48 x 1" is correct since he seems to be referring to the small bolt in the bottom right (and top right) of the door skin on mid-60's Bally doors starting with Rocket III (Apr 1967) through Mariner (Nov 1971). The bolts holding the perimeter door trim are # 8 and have the square shoulder on the back side of the head.
These are not new bolts...I chuck the original in a drill and sand first with 220 grit then 400 grit paper then buff to a mirror shine.
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