I too worked at a shop a little over 10 years ago when 1500 and 2000 were "fine grits." I am sure the tried and true will work, but I was researching dampsanding to get with the times and bookmarked this site:
I am pretty sure I watched youtube videos by this author as well, and it was quite informative. it is amazing how the paint starts to shine as you get up to 5000 grit.