I got the Polara 500 and it has the wrong block. So I found a 361BB which has S36 then HP and the bottom looks like a 2. (I already checked the casting numbers that are on the bottom, 2205712.) Is the bottom supposed to be a letter or number? I cant read all of it from the picture so I need more eyes. What does the HP mean? Also does anyone know about these engines? Is it worth fixing for an original car or is it a boat anchor? The one I found is $300.