i have had my revo for about 6 months now and its wifi signol is always at low/very low.
this instructable is easy and requires very little skill and no soldering.
Step 1: things you need
going clockwise all the tools you need.
wera esd screwdrivers(any old screwdrivers will do)
a drill or brace.
the wifi pigtail lead(can buy of ebay for about a pound i got free shipping from china