This is can of worms.The markings were intended for both.But in the real world Its more to do with the unit,and even down to the driver/drivers mate.
There thousands of combo's from 2' high to 2" tall.
In gaming terms Do what you feel looks right for you,and use the unit markings you put on your figures,and you can't go far wrong.
A fair rule of thumb would be early war go to town,Late war little or none.