Ok not a problem. Its very possible I myself have done it several times. First you're going to need the SBF flash file for the .604 OTA, along with RSD Lite 4.7. You can get them from this download link:
Multiupload.com - upload your files to multiple file hosting sites!
Next you're going to extract the SBF file (its about 430MB) to somewhere easy to find, like your desktop, and install RSD Lite. After you finish installing RSD Lite copy the file from the RSD Lite zip named "pst_flash.ini" and paste it over the old file in the C:\Program Files\Motorola\RSD Lite folder. Your directory may look slightly different depending on drive lettering and whether or not you're running x86 or x64 Windows.
Once that's done, shut your phone off by holding the power button and then hitting Power Off. Once its off, you must hold the following two buttons: Camera button (push all the way), Volume Rocker DOWN and then with both of these held down press and hold the power button while still holding the other two buttons. Once the screen goes on you can let go. You should see a black screen with some white text on the left side saying Bootloader. That's when you know you're good to go. Now hook up the USB cable to your phone and PC then load up RSD Lite.
You should see a device listed in the #1 slot on the list. If you don't then that means your drivers aren't installed properly for your phone and you'll need to install them (they're inside the zip file named "the_gift.zip" so you should have them)
Now with that done and you can see the device listed in RSD Lite, click the ".." button to find the SBF Flash file you extracted to your desktop. Open it and hit the Start button.
ONCE THIS BEGINS YOU DO NOT TOUCH ANYTHING. Not your phone. Not your PC. NOTHING. It is completely automated all the way through.
At some point its going to reboot your phone. Now one of two things can happen here:
1) It reboots perfectly normal and gets to the Droid OS and the process is complete
2) It gets stuck in a boot-loop saying "manually reboot your phone 100%"
If you got 1 then you're good to go. I suggest you do a Factory Reset and you're good as new.
If you got 2, ,make sure its a boot-loop and not just taking a long time to load. My first SBF flash took about 10 minutes on the red droid eye and I was tempted to battery pull but I was patient and it worked perfect on its own. If it says "droid" then you see the eye, and all of a sudden the screen flashes and it goes back to "droid" and the eye, you're in a boot-loop and then you need to unplug your phone, pull the battery out so it shuts off then pop the battery back in. Once its back in you press and hold the HOME key and then the power button. Do this until you see a little Droid with an Exclamation point. Press the search button (farthest to the right on the bottom) and then use the volume rocker to go down to "reset to factory" and then press the menu button to hit OK. Let it finish this process. Once its done, volume rocker back up to reboot and hit OK.
You should now be perfectly good as new. It will ask you to activate your phone. Go ahead and do so. If it doesn't work and that your phone cannot be activated its ok don't panic. Just wait a little while (my first SBF flash and factory reset from 2.2 required me to wait about 20 minutes before I could activate, its a problem on Verizon's end not your phone)
Once its activated and at the home screen you're all done. Good luck