Car class lettering for autoX?

Hello,
i just wanted to check vcmc's convention for displaying the car class at an autoX event.

I have magnetics for my # as well as for 'S' for stock. Do I need the full class letters (eg. HS)?

thanks!
an.

[Cliffy]

Both #'s and full class letters are appreciated. Although our timing and scoring computer doesn't require them, complete car designation is encouraged so that the course marshals can identify your car.