First, please see my comment to the question.
I think you are approaching the problem from the wrong side. It looks like you think that those different libraries are
holological (in this sense:
http://en.wikipedia.org/wiki/Homology_%28biology%29[
^]). They are not! (Oh, thanks goodness!)
The approached are too different, first of all, because the systems and technologies (if one can VB6 features a "technology"). In a nutshell, .NET libraries are pretty good and different; and VB6 is something which was completely wrong at the moment of its creations, much, much worse than many much older languages and libraries.
The migration is possible, especially of VB6 legacy code is written very accurately, which is rarely, almost never a case (a decent developer usually would not agree to deal with VB6).
Please see this discussion:
http://social.msdn.microsoft.com/Forums/en/vbgeneral/thread/caea0ff1-7177-48bc-88cf-4db4f326a0ef[
^],
http://msdn.microsoft.com/en-us/vstudio/ee373823[
^].
If you Google, you will be able to find some solutions for automation migration.
I personally know some very intensive attempts to migrate using some automation. I don't know a single success story :-(
The right approach would be to learn .NET approaches from scratch, trying to free yourself from the ideas you might have been preoccupied with.
—SA