i was assembling my lower last night. it was my first and it went realy well...aside from having to chase the damn buffer retainer and spring across the room after they shot out, but i found em.

i did everything good, and checked every thing for function...it all works great...but then as i was going over the bolt catch one more time i saw some nasty blue plastic that was inside my stag rollmark.

i taped the parts by where i put the roll pin in, so i didnt scratch anything, but i think the blue plastic is from the handle of the punch that i was using to drive the roll pin.  does anyone have any idea as to how i can get this stuff off??? i tried some light scrubbing last night..buts its pretty well in there. i dont want to try and dig it out becuase i took alot of time making sure i didnt screw up the finish while i was assembling it. any ideas?

Use a toothpick.

good idea...i feel stoopid now.