Thing is only two of the 3 mounting holes are attached to something. The 3rd/ rear hole is hanging over the hole in the top.A 2x6 is strong enough to work and you can add support underneath without harming the surface.
Heck, I used drywall screws and a cheap particle board desk for awhile and it worked. Just swapped stuff around with a cordless drill.
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If he doesn’t want to drill the top, just bolt the press to something he can clamp to the top.
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If the object is stout enough for a person to sit on and not move, it will work for reloading.