netbsd32 X11 libs for amd64

[coypu%SDF.ORG@localhost]

I'd like to build a package that uses 32bit X11 libs on (netbsd) amd64.
at the moment at least I am missing freetype which is 32bit.
I've tried to create emulators/compat70 and emulators/netbsd32_compat70,
but I'm confused about the distfiles I need to make in LOCAL_PORTS - why
does it not use just set tarballs (and from their origin)? how should I
put my own there?
thanks