iPhone 4 wifi chip metal plate remove

HI

as the wifi of my iphone 4 is not working anymore after a waterdamage I wanted to know, how i can reach the wifi chip on the mainboard right above the A4 processor chip...

the metal plate, which is potecting this area seems to be fixed..

is there a way to remove this metal part to clean the board properly in this area...?

how else can I clean the wifi chip on the mainboard

at the moment is is greyed out..

thanks in adavance

cheers