Sticking covers and blanking plates on etc depended on how long you were going to be hanging around. If the cab was parked for a lunch break, nobody gave a stuff - overnight was rather different. However, again there were certain criteria depending on weather etc.
Leave the cab on the ground alone, it might just be there for a short time.
In my experience, most people who want to nit pick are those who have never 'done the business'.
Old Duffer