I believe you will find the answer in the rather brilliant (at least I thought so) article "Reset and Remove Applications in Location Services on Mountain Lion (dated Jan 5, 2013)".
You'll find "clients.plist" in "private/var/db/locationd" which you have to convert to xml1, edit and then convert back to binary1, then kill locationd. All steps are explained, save and except you have to identify for yourself which text to delete specific to the application you want to remove from Location Services.
For me this text was:
<key>org.kismac-ng.kismac</key>
<dict>
<key>Authorized</key>
<false/>
<key>BundleId</key>
<string>org.kismac-ng.kismac</string>
<key>Executable</key>
<string>/Applications/Utilities/KisMAC.app/Contents/MacOS/KisMAC</string>
<key>LocationTimeStopped</key
<real>382473182.77373999</real>
<key>Registered</key>
<string></string>
<key>RequirementString</key>
<string>cdhash H"0b90033c15e7ad07d0b715d8fb20a3b84caf2ac9"</string>
<key>Whitelisted</key>
<false/>
</dict>
Many thanks from me to the author Sayz Lim.