I am rebuilding a 1966 Scout. It has a 152 in it and needs a new head. I have looked everywhere for one and it seems like they don't exist. The casting number off mine is 216368-r2. I found a head on ebay but the number was different (216365-r3). Will this head work? What all kinds of heads will work for it? Do you have any tipps where I could get one?