The radiator support from my 51 3100 was fastened to the frame with two bolts spaced 8-10 inches apart, but it had definitely been "tampered with". It had a piece of 1/2-inch thick steel wrapped around the bottom in place of the normal sheet metal standoffs.. The steel wraps about 6 inches up each side and I'd guess it weighs more than the whole original unmolested support. They had a strip of rubber between the support and frame, also about 1/2-inch thick. Definitely overkill on the repair. I've seen pics of the repop supports with the wider bolt spacing for what that's worth..
