You don't NEED Amon's recovery. You need it if you want to "automatically" install the new ROM from Fresh Updater. But forget about that.
Instead, just download the update file. When it asks you if you want to update now, say No.
The file will then be in your SD Card/Download folder. Reboot your device into Fastboot by holding the down arrow and power button. Then choose Recovery.
If clockwork is correctly installed on your phone, you'll be at the custom recovery screen. One of the options is to install a .zip from the SD card. Just navigate to the Download folder and install the zip that way.
That's how I do it, and I have premium Rom Mgr. Who wants to screw around with having to flash different recoveries and all that? Just reboot the phone manually.