Well, IIRC the book rate for this fix is 3 or 4 hours (trying to remember back to 1997 when I had it done). Assume Ford underrated the rate by 25% (to screw the dealers and save $$$ on paying warranty work). The $400 doesn't seem so unreasonable any more. (What does your local Ford dealer charge?)
I do know that under pressure (from me), a Ford dealer did the work on my car between 9 AM and 1 PM on a Saturday (5 hours).
By looking at the Service Manual, removal of the tank and filler pipe doesn't call for anything special in the way of tools. Either drain the tank or run the fuel as close to E as you dare.
