How do you assign numbers to the race modified cars?

[cryptomanic]

This may seem silly or I am missing it somewhere. I have looked through car settings but could not find where to number the cars. I did a search but came up with nothing.

 

[Blitz24]

This may seem silly or I am missing it somewhere. I have looked through car settings but could not find where to number the cars. I did a search but came up with nothing.

Garage, then select the option of car number.

 

[cryptomanic]

Garage, then select the option of car number.

Thank you so much