I have had a friend ask what the best method would be to weld his water cooled manifold on his boat would be. I haven't seem the hole, but he claims it is on the outer jacket, and looks like a defect in the cast metal to be1/8" x 1/4" slot. Apparently the metal is alot softer than a typical car manifold. I have recommended using a stick welder with a nickel rod, do the whole weld in one pass, and peen the weld after it has been done. What would be the best nickel rod for this process and what size (material thickness is slightly less than 1/4"). I have also told him to make sure the area is clean, and dry. Apparently the part isn't so expensive, but very labour intensive, so if he was able to weld it it would save alot of time and money. He plans to clean up the area with a dremel tool as it is too small for a grinder to get at, and cut the rod in half to perform the weld. Any recommendation would be appreciated. How difficult would this be for an beginner/intermidiate welder.