I'm surprised that Gotoh didn't offer a Musicman / G&L version of the Resolite given that there were MIJ G&Ls and the Musicman EX series.
Ultralites will leave visible screw holes but only you will see them, although you could use HB1 tuners. Not as light as the Ultralites but possibly lighter than the originals.
Out of curiosity, how light is your Sterling that it has neck dive? Mine is 10lbs but feels lighter as the neck points slightly upwards so I never had an issue with neck dive.