So far, these are the steps that I *think* are correct:
1. Pull /system/framework/* files onto my PC.
2. On the PC, baksmali the services.odex.
3. Makes the changes to whatever .smali file I wish.
4. Rebuild services.dex via smali (using the output dir created by baksmali).
5. Insert services.dex into services.jar (using, say, WinRAR).
6. Push the new services.jar onto /sdcard and then copy it over to /system/framework dir.
7. Reboot and pray it works.
Is this correct?
EDIT: See my reply below for the answer.