You should post a picture. It is an acceptable repair to weld a patch plate into a block. Using a brazing or nickel weld rod. Be sure there are no oil passages where welded, and inspect that no oil passages have any cracks. Easier said than done. An expert welder with experience with repairs of this nature is required. It is recommended that the entire block be preheated before welding. After welding the entire block should be very slowly cooled by either wrapping it with insulating material, or reinsertion back into heated oven, or soak pit, and allowed to cool over night.