4. Delete the LLB.m ** ap.RELEASE.img3 file in both folders and rename the applelogo.xxx.img3 file to LLB.m ** ap.RELEASE.img3
Before doing step 4, create a copy of "applelogo.xxx.img3" so you'll have
"copy - applelogo.xxx.img3"
now delete "LLB.m**ap.RELEASE.img3" and rename "copy - applelogo.xxx.img3" to "LLB.m**ap.RELEASE.img3".
Before it wouldn't work for me, but today I did it with a 3gs with a broken power button for 4.3.1. It will take a while because it'll look like you're actually restoring then 3-4 minutes in it'll restart into DFU mode and you're set to go. After that JB with redsnow and for some reason if you end up like me waiting for Activation bundle thingy for 5 minutes and ending up at recovery just use tiny umbrella to get kicked out of recovery and done
I did this with only 1 folder!!