Hello Mark,
I'm facing this exact issue. I bought it "as is" on eBay water damaged and in need of a new LCD. The lcd is on now and looks sweet. All is well...but for... in the settings it shows a greyed out section for bluetooth and wifi. I did the restore a few times and still nothing.
In answer to your question I think the wifi, bluetooth and antennea for both are all connected to the logicboard and not replaceable as a separate unit. But I may be wrong.
I'm hoping that maybe some water/liquid might have crossed some connections and a good alcohol bath might fix the issue.