Those look like inserts/timeserts
They’re usually pressed in, as you can see most likely they were pressed in at the factory, at the desired hight.
I would totally cover the holes with masking tape, or find 2 bolts of the same pitch, screw them in, or better yet find a bolt with a wide head that will match the flat side of the thread flush, screw it in, tape the end that will stick out the other side and remove them when powder coating is finished, cut and trim with a brazor blade some of the burr, left over paint so that it won’t chip away, not to mention it will look neat.
Hope that helps.
November 15-19, 2017
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