If you don't want to take the screen off take it somewhere with a big air compressor and shoot it around the edges/bottom of the display. Don't be a tool and go full bore right from the start, gently blow around it gradually increasing the pressure and see if you can at least move the damn thing from the center of the screen.
ifixit.com will tell you how to take your screen apart though if you want to just try and DIY.
I had a look at the iFixit instructions for removing the LCD.
I would really like to avoid all the hassle of detatching the screen from the body of the laptop.
Do you think it would be possible to skip those parts and use a heat gun+suction grip to loosen the area around the top+top2 corners and then just blow from a little opening at the top?
yesterday 29.6.2013 at 21:00 i saw a insect walking on my screen i thought is on the screen ,but no,he walking on the screen from inside ,
today i see two R.I.P insect.
I've also had this problem. Just taken my Late 2013 model MBP to the apple store. Luckily my mac is still under warranty so they've replaced the entire top part of the laptop. If it wasn't under warranty it would've cost me £286 for the repair.