Hi, this is my first post
The finger Montesanto is on about fits on the motherboard.
Just above the right top corner of the front facing camera you will have a screw which originally would of had a piece of black tape covering it, this finger acts as an earth on the chassis and fits between the board and the screw, NOT under the board, the black tape is also important to shield the top of the screw from touching anything.
The earth for the rear facing camera is also important Sylvia as are all the components that make up an iPhone.
I'm not sure but i think some parts are for the wi-fi and mobile signal circuit but i cant be sure.
I hope this helps and if you need photos of positions of fingers then just let me know.
Hey Montesanto, check the screen and digitizer connectors on the board as sometimes if you press too hard and unevenly you can flatten out the soft solder on the connector and the pins touch therefore shorting out the screen, use a magnifying glass and scrap the solder from in between the pins very gently with a tooth pick, also check that the Yellow Kapton tape is covering the two small power points on the screen ribbon cable, they are the ones you would use to put a backlite led behind the apple logo on the back and they can sometimes touch the board giving a short.
EFF rules KO!