Here is a shot from the intake manifold side. Note the blocked of idle air passage.
Here you can see the difference in the bolt mounting patterns and sizes between the DBW and DBC systems. It's light, but enough to make it a headache! and the DBC TB's holes are not square, but rather a rectangular array just to make things that much more difficult.
Gaskets overlayed. The holes line up better on the gaskets because they are all oversized. This isn't a true representation of how off the holes really are.