It is possible to over-tighten these screws, causing the home button to malfunction.
+1 on the right 3g antenna - it is adhered to the glass and I cut right through it with the opening pick. The replacement included adhesive to re-stick it to the glass, so this is a definite feature of this antenna. This is a thin film similar to the wifi antenna, so maybe going around it at a shallow depth from the corner to the camera and then returning to the corner slightly deeper would allow you to separate the antenna from the glass without damaging it.
My CDMA iPad 2 has 2 antenna wires for the left antenna, was a little different than pictured. The short wire nearest the headphone jack attached to the second silver connector from the left of the board (when board is in its proper place). The long wire attached to the left-most connector. I had to fully mobilize the board by removing the 4 screws that held the wifi antenna to the bottom of the iPad and then flip the board upwards in order to re-attach all 3 3g antenna wires.