New aluminum radiator in my '69 BB Chevelle. It sits level in the rubber mounts on both sides, but along the bottom, about 8" in from each outside edge, the radiator has direct contact with the metal support. Is the radiator supposed to completely "float" in the rubber mounts, or is it okay to have it touching the metal support underneath it? I don't want this radiator to get rattled to pieces.

Thanks for any advice.

I would say that would depend on if there was any movement in the radiator. If it can't move then it can't chaffe through. If you are concerned then you could possibly use a piece of foam weatherstrip and place in it.