Just tape off the grille and remove the bumpers, that's all I ever did with my '40 and I held the record from 1975 until BMR came along. I was lucky I could also take off the headlights.
Putting a step pan under a car with all the stock type stuff hanging under it would be a real pain that is why I never did it. If you have enough power i won't realy matter unless it it required, Jimmy Stevens left everything under his street roadster and just removed the fenders and headlights for the gas/roadster record...............good luck glad to see that car coming back