Re-enable full auto on HFC M9

[lbonney]

Hi guys, i just got a HFC M9 where the full auto has been disabled, i was told it was easy enough to do with a piece of scrap metal from a coke can..... Im not looking to grind down the trigger bar, but there must be another way to enable auto.
ive searched youtube but cant find much, Any help will be much appreciated!! Cheers