my way (iirc, it's been a long time) to create the "installer"
packages for OSX systems is something like:
$ [...]
$ make install DESTDIR=/tmp/foo
$ mkdir /tmp/Gem
$ cp -rav /tmp/foo/usr/local/lib/pd/extra/Gem/* /tmp/Gem/
$ cp -rav /tmp/foo/usr/local/include/Gem /tmp/Gem/
$ cp ${ALL_DEPENDENCIES} /tmp/Gem/
$ for i in /tmp/Gem/*.so; do script-to-make-deps-local ${i}; done
$ ./build/osx-dmginstaller/buildinstaller.sh /tmp/Gem/