Modding city sizes on a Mac?

Normally a city at its max size has a total of 36 (I believe) individual workable tiles. I was wondering a) if that can be modded, b) which file(s) need to be edited for that to happen, and c) where those files would be located on a Mac.

Thoughts? I searched through the modding section of the forum but couldn't seem to find anything that addressed this particular question.

Also didn't know if I should've posted this in the Customization subforum or the Mac subforum, so apologies if I shruted it.