The white cable is an assembly of 2 cables with total 4 connectors - you need to replace as an assembly if you think it is faulty
See [http://www.repairsuniverse.com/iphone-2g-wifi-cable-replacement.html|HERE] and zoom the picture
This [guide|599|GUIDE|page=3] should assist in replacing the Antenna module - specifically from step 21.
The module is likely held in with double sided tape. Something like [http://www.officeworks.com.au/retail/products/Office-Supplies/General-Stationery/Adhesives-Tapes-and-Glues/Tape-and-Tape-Dispensers/Double-Sided-Tapes/3M0061044|THIS] may be suitable for re installation.
The white cable is an assembly of 2 cables with total 4 connectors - you need to replace as an assembly if you think it is faulty
See [http://www.repairsuniverse.com/iphone-2g-wifi-cable-replacement.html|HERE] and zoom the picture
This [guide|599|GUIDE|page=3] should assist in replacing the Antenna module - specifically from step 21.