[SeanPaintsFlames]

Actually, if you don't have a welder but need small holes filled, get a pointed body hammer. Sand or grind the hole. Put the hammer point in the hole. Hit it with another hammer. This puts a dimple in that hole, so you actually are going to wipe filler into a dent rather than just a hole, giving more surface area for the filler to grip. If you can spray primer on the backside of the hole you're golden. I've done this and it lasts.