I took some pics of my 3 screw's board for comparison. There are some chip differences as well as a difference in the board designation altogether. My 3-screw has NES-UNROM-09 printed at the top, the 5-screw says NES-UN-ROM-06.
The front label is identical so I didn't bother with a pic. Also, as mentioned before, this MM 5-screw isn't a first print, it's a Rev-A and says so on the back sticker.
Hopefully this info makes it harder for people to fake (since a winning bid like that is bound to draw some of the wrong attention)
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