It's cool to be square.
look at harry potter. why not save yourself the hassle and rid the 16 as Soichiro Honda intended and keep that beautiful designed classic that sets it apart.
another point to remember is that the 16 came before the 18, 21 and 28 and contrary to popular belief is the DADDY of the nsr family. look at the spencer rep on this site, which clearly states what i am saying (Top of the table, okay not quite standard but who would know? he that does know will be too busy standing at train platforms numbering the frieght wagons, while mr smooth is stepping in on their lady with an mc16 running classic.) by those in the know.
keep it square and it might put a bit of magic back into your life. I'm proof cos people look at that square chunk of eighties and can't wait to ask me what the 'hell' i'm riding that for, when the done thing is to go gp pointy angular smooth aerodynamic...now square doesn't seems square and by the book. Make your own rules get square.
plus if you are fast, which i don't doubt then most people will not see it passing, just don't stop and those following you on a track day will not be concentrating on the task of overtaking you but wondering what the 'hell' you are doing riding a bike with a rear whose designers spent to long relaxing in the back garden overlooking a small garden pillar wall.