I have an Astro van with a v6 in it now. It is fairly common and easy to put a 350 v8 in it - the v6 is simply a v8 with two cylinders chopped off. I read in a couple of other forums that the 6.2 was designed to slip into the place where the 350 came from. Is that true? What about the block size of the 6.5 and 6.6?