I finally put the Galaxie back on the ground and turned the key tonight on my C6 to close ratio toploader conversion. Things went pretty well, except for a ground issue that is presently evading me; it's not horrible, but slow turn signals, no fuel gauge or horn, and an electric fan that sometimes cycles when key is off and hazards are turned on--weird. Other than that, it runs well with the 3.89 gear, though only ran it up and down my road a couple times--the Ford shifter isn't the greatest, with 2nd to 3rd being an adventure when I was taking it easy, but a spirited run and it shifted quite well.
Thanks to all on this site for the wealth of information that assisted me in the conversion.