But for finishing it 400-600 grit is probably good.

Here is what it should look like, red line is the mod. A very small mod. Sorry for the crude drawing.

[Linked Image from i235.photobucket.com]

That little sharpened point will allow the hook to catch underneath the cap.

JYD #54 "Put your hands high, let your arms be the pillars that be holding up the sky..."