Hi BigJoeJack, I have seen many older Defenders with checker plate at the bottom of the doors and vehicle. From what I have read, many times it is because this area rusted out and it was away to cover it up. I for one think it often looks good and can serve as some protection too. Since the door skins are aluminum, using anodized aluminum diamond plate and aluminum rivets would work and be similar metals would not have galvanic corrosion. You would need to seal the top and side edges to prevent moisture from getting trrapped and allow a portion of the bottom to not be sealed so any trapped water could drain out. DaBBull