Thanks so much to everyone for your help. There seem to be a combination of factors that have added up to a no charge condition. First, the ground bolts were heavily corroded, second, the fuse was heavily corroded, third, the fan belt was somewhat loosely tensioned and the bolts holding the alternator (which we replaced) were not very tight.

We have one more ground to clean up, but a high-end SnapOn tester shoes that after hunting down all of the above issues, we did have a working charging system. Thank you all again.