I have a later dated manifold exactly like that but dated 1977. I know where mine came from. A motor home with and original 360. I assumed they continued casting that pattern for RV and other odd applications. Dan
Thanks for that 75Sport. It makes a little more sense now!! It's funny that the Mopar exhaust manifold casting number chart doesn't show these used on motor homes. So I guess Mopar used them where ever they needed a little more power (like a motor home).
