Adding Kinetis boards

Hi,

I am looking at adding the Kwikstik to the current Kinetis boards, and I
am wondering what would be the best way to approach this.

Currently there are two Kinetis boards, the TWR-K40X256 and TWR-K60N512,
with the directory structure something like this:

kinetis/var/...     - Generic Kinetis code
kinetis/twr_k40x256 - K40 and twr-k40 code
kinetis/twr_k60x256 - K60 and twr-k60 code

Kwikstik is based on the same MCU as the twr-k40x256, so it needs the
same MCU-specific code as the twr-k40x256 board, which I think is all,
or nearly all of the code currently under the twr_k40x256 directory.

I initially thought I'd just clone twr_k40x256 into a new kwikstik
directory, but that's probably not the best approach for
maintainability. I am thinking it might be better to split out the
generic K40 code so it can be shared between distinct boards, but I am
not sure where to split this to: should there be a separate k40x256
subdirectory and a corresponding package that the twr_k40x256 requires?
Or is there a better way of approaching this altogether?

Many thanks in advance,

Tomas