So my reason for wanting to root my phone was only to remove unwanted apps that were pre-loaded. Other than that, I was much more comfortable running a pure stock ROM. Right now, I'm running pure stock unrooted FRG01B, but with all unwanted apps removed. Here's how I did it:
1. Downloaded the full FRG01B master OTA file (9046f5a3ec09.signed-voles-ota-45394.zip)
2. Deleted unwanted APK and ODEX files from /system/app inside the ZIP file.
3. Flashed stock 2.1 SBF.
4. Flashed SPRecovery.
5. Installed my modified update.zip.
6. Cleared data.
What I have now is stock unrooted FRG01B including stock recovery (the update.zip will overwrite the recovery and the baseband in addition to the system ROM). The difference is that things I don't want like the MP3 store, Gmail, Facebook, etc. are removed. If you're wondering why I did it this way, the answer is: because I can.