400 big block + my 71 Demon

1970 and 1971 383 magnum manifolds fit if you trim the column back to the fire wall. 67 - 69 manifolds do not. the flange that hold the pipe is at a different angle. You can also use the 70 71 motor mount brackets with small block dodge pickup biscuits mounts. I have done several like this you only need to trim the K member for the Oil pump. the rest is bolt in parts from the correct cars. RB blocks do not fit this easy. The deck is to high. Steve