What am I doing wrong?

I'm currently running my ATV2 jailbroken with Pwnage Tool and aTVFlash beta 4 and firmware 4.1.1. So I downloaded from iClarified the latest ATV2 firmware ipsw file version AppleTV2,1_4.2.1_8C154_Restore. Then I got the latest Pwnage Tool 4.3 which claims to JB untethered now. So I run Pwnage Tool 4.3 and Browse to my Desktop where I have the AppleTV2,1_4.2.1_8C154_Restore.ipsw file and Pwnage Tool says "Wrong Firmware Bundle" selected. Do I first have to restore my ATV2 back to the latest officlal firmware via iTunes before I start or what?