Question about building iPXE with named configuration

[pxe_curious]

I have been building iPXE undionly.kpxe and snponly.efi binaries for a while now.
There are some features I need that are not in the default build and some features I really do not need.
To get the build I want, I have been modifying the console.h and general.h files in the src/config folder. I have to really keep two sets of the general.h file, one for PCBIOS and one for EFI.
I realized from the get-go that my manual workaround for this is cumbersome but didn't think to check if there is a better way to do this.
I recently saw the named_config article but am not really sure how to use it, though I think this would solve my issue.

My question specifically then is:
Should I copy the edited versions of console.h and general.h files into a named folder into the src/config/local folder and leave the originals untouched?
Or is it sufficient to place respective text files with just the changed lines in the named local folder?
Would I need to add an explicit #undef for features I do not want?