I know that how it work n cars that the 10th digit is the year but it looks like it is not the same for motorcycles. There is never a O in a serial number its always a 0 and they never use I's either.
I had the same exact issue but eventually just used a smal piece of cardboard to hold the nut up. I did this after I dropped one of the square nuts down into the abyss somewhere and could not use the old nuts or bolts because they did not fit either. I ended up blowing compressed air all around...