I pulled the dash apart yesterday to change some bulbs myself. Had the same problem with the speedo cable, but it came loose after some pulling on the speedo unit. To attach it back I had to access it from underneath lying on my back in the footwell under the steering column. You can see the tip of the speedo where the cable attaches from that angle and makes it much easier to reattach. Just push the cable back onto the speedo. It clicks in place, you'll hear a click. Hope this helps.
Also, couldn't find the bulb at Autozone, so I went to the local stealership. They didn't have either and claimed they could only order in quantities of 10...Said Ford ahd discontinued the bulbs.............Its a crappy stealership.
