saw i determined that the bottom of the plane was already as flat as it needed to be. i still wanted to clean up the bottom and sides though so i stuck some self adhesive sand paper to my table saw and gently cleaned up those faces. i also made sure to sand the long edges of the plane where the sides and bottom meet to remove any sharp corners that could more easily damage a work piece during use.
the end result of the sand paper was good enough for me. here you can see the #5 on bottom and a relatively new #62 low angle jack plane on top.
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