The thing about using kits and such is that the mids already have enclosures. I am going to deaden a little bit of the inside of the factory enclosures and obviously do the same to the pods that I make for the second set.
Making the second pods is going to be interesting. I'm going to have to fill the existing pods with styrofoam to get the internal volume and then duplicate that volume in a different shaped pod. That way both pods will be ported.

I'm also planning on incorporating the grille for the first mid in with the pod for the second mid.
Saying it will be interesting isn't even scratching the surface!