I seem to be out of the woods (after more than 20 hours). Carbon Copy Cloner was the answer. I now have a bootable copy of the SSD drive on the MacIntosh HD. I am on the 30 day trial, but I will buy it. Time machine may be enough for files and directories, but it is not sufficiently reliable for restoring the entire system. I will use Carbon Copy Cloner for weekly backups. It costs $39.99.