I noticed Chirp is requiring OS X 10.8. (or latest version).
I don't believe that the above statement is true.
The CHIRP download page states...
"New Mac OS X must install the runtime once before running CHIRP. After it is installed, the runtime does not need to be downloaded or installed each time. Download the KK7DS Python runtime for Mac OSX."
In this case, "new Mac OS X" doesn't mean "latest Mac OS X". In this it means a "Mac OS X that has never had the KK7DS Python runtime for Mac OSX installed".
it also states...
"OS X support is limited to Intel architecture. PowerPC is not supported."
So if your Mac has an Intel CPU, and you have satisfied all of the prerequisites mentioned on the download page (and have a properly installed and working programming cable), CHIRP should work for you.
Jim KC9HI