popeye glad you got her all fired up with that Mustang ICM. :)
This old stuff tends to keep our brain cells more active which is a good thing I read. There seems next to no one in business that worked on these early computer controlled firing and fuel systems of that era.
As other articles and Chuck points out PCM's seldom fail so that is one reason no one suspects to look at that part. Glad there was not programming or flashing required. These early computer systems were quite simple in features but they were a step in the right direction.
We have some kind of computer box on the old 1989 ford F700 two ton truck and I hope it never fails. :)