Just picked up 2 409’s. One has this number T0525QG. 191060. 656 block. It is single 4 barrel, aluminum manifold. The other has no stamping whatsoever? It is 814 block, aluminum manifold, single 4 barrel. 656 manifold is 3814678, 814 manifold is 3844463. I thought I had a 340 hp 63 and a 340 or...