Hello Stuart,
Using diamonds like roger said is the way to go-you may have been able to get the deep scratches with 120g on your floor machine.
Then use 220,400 and 800 if you want more clarity.Then polish with a quality polishing powder like 5x or what ever you are comfortable using. Was it MB-12 you used-16 is for granite.
Mb-12 should be used wet to dry-takes some practice to get it.Also requires a stronger machine.
Honing powders work well when you want a honed finish-cant beat them for that.
Using them to prep a floor for polishing in conjuntion with norton pads will give you a wax like finish when you polish. The fiber pads simply dont work as well as resin diamonds. Yes they have their place for sure but I dont think they can match factory finishes.
With polishing powders you can in some cases do better than factory polish.