I read your post from page 1 to page 3. It sounds exactly like what my truck has been doing, of and on for about a year. I have changed the timing belt, plugs, wires, ignition coils, MAF, O2 sensor. None of which improved the performance.
The problem has continously got worse until it would hardly run last week. I took it to a mechanic which has a good reputation for troubleshooting electrical issues. In less than an couple hours he diagnosed the problem. It was the ignition contol module. $250.00. I picked the truck up Friday and it is running about like it did when I bought it in '94.
The mechanic told me there were still some codes in the computer which shoud MAF sensor isssues. He said this was common w/ Fords.
You may want to find one at a jucnk yard before you sink $250 in a new one. Hope this helps you. Let me know if this fixes your truck.