Visual only on what they look like, left is what a 6 Cycl looks like and Right is what a V8 looks like
The V8 on the right has the larger bell and foil
the pic is fully converted, you can see where i have ground off the welds on the one on the left and swapped over the heat shielding and quick coat of paint black to protect the spot welds,
i just use a mig, arc welder would be maybe be fine, not sure