Level of complexity is going to vary greatly depending upon how deeply the core is buried in the dash. I had a Ford Bronco II that you could swap out the heater core in about the same time it took you to change the oil, and I had a Passat that took days. I'm convinced VW started with the heater core as the main structural center of the vehicle, and then built the entire car around it.:razz:
No way to know for sure without a look at a Haynes or similar, or finding an online forum for Ford passenger cars. Here's a likely one to use, but I think you have register with them before they let you search.
http://forums.thunderbirdforum.com/forumdisplay~f~8.htm
A quick google turned up this quote from a backyard mechanic
"it is quite easy to replace the heater core . all you need to do is open the glove compartment and pop-off the hydraulic hinge and pull the glove compartment all the way down and you take off four bolts on the plastic cover and it comes right out."
YMMV, other "experts" may have different opinions
Normal garage tools, nothing exotic likely needed, although you can avoid some mess by pinching off the heater hoses to avoid spillage, and there are hose clamping pliers made just for that purpose.