If I had to clean-up the Slider Pin Bore, I would prefer using a 6-flute Reamer.
You would get a nice round hole.
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Have you ever used a 2-flute drill on sheet-metal ? / The hole has a triangle shape (3 sided).
The Pins, I would clean up on Wire-Wheel and file if needed.
Depending on condition of pins, replace if questionable.