This is the bottom view of the manifolds. You really won't see any difference here at all except for the increased webbing and slightly increased runner size on the 2nd gen manifold, seen at bottom.

Not a lot of difference here, until you realize I had already ported the 1st gen manifold, and its' intake openings were about equal the as-cast 2nd gen openings. Also, the flange around the openings is beefier on the 2nd gen manifold.

This is where the differences are a little more apparent. If you look at the front bolt through-holes (red markings), you'll hopefully notice that on the 1st gen, the flat pad that the bolt head rests on is above the surface of the 3rd runner, while the 2nd gens' pad is machined into the manifold surface. You may also note on the rear holes (blue markings), the 1st gen pads are much higher than the 2nd gen. This is because the top of the 2nd gen manifold comes to a higher peak in order to better aim the exhaust gases at the turbine blades.

On this pic, the blue markings are again pointing to the height differences of the bolt pads. The red markings point to reinforcements added to the heatshield mounting points, although why I don't know, as I have NEVER heard of a manifold cracking at those points. The pink markings point at the center of the manifold exit, to highlight the more obvious depressions between runners. This helps show how the runners were enlarged upwards to get more flow and aim the output.