Keyboard remapping in OS X 10.9
The easy way to do this would be to use Keyboard Maestro and just create two macros, one for 'q' which inserts '`' and one for '`' which inserts 'q'

It also does a ton of other awesome stuff and is one of my favorite OS X utilities, but it’s not free (there's a free trial 30 days it’s ~ $35 IIRC).

However, my guess is that you could also do it using KeyRemap4MacBook using the private.xml feature under "Misc &amp; Uninstall"



I am not qualified to explain what needs to be in the private.xml file, however, I can point you to the documentation for
A simple example of private.xml which shows some examples and explains the format of the file.

There is also a free Mac OS X app Key Codes which you will probably want to use to help you find the correct key code values.