Use install's relative symlink feature to create uniquefiles.

[mat]

Summary

Before, the symlinks were created as absolute paths, so it would look like this:

# ls -l /usr/local/bin/
[...]
lrwxr-xr-x  1 root  wheel      12 Apr 14 14:28 autopep8 -> /usr/local/bin/autopep8-2.7
-rwxr-xr-x  1 root  wheel     395 Apr 14 14:28 autopep8-2.7
[...]

After, the symlinks are created with relative paths:

# ls -l /usr/local/bin/
[...]
lrwxr-xr-x  1 root  wheel      12 Apr 14 14:28 autopep8 -> autopep8-2.7
-rwxr-xr-x  1 root  wheel     395 Apr 14 14:28 autopep8-2.7
[...]