Trouble rooting samsung galaxy s3 tmobile

So i surfed the net on instructions on how to root this phone. I downloaded Odin and the Tar file. I did this step successfully

but when i go into CWM to install the CWM-SuperSU-v0.87, it tells me "signature verification failed"

now this is not my first time rooting the phone so i know to toggle the verification thing off

but the problem i have is i dont see the DAMN OPTION. all i see is apply from sd card, reboot cache wipe, and paritition but NOWHERE DOES IT SAY TO TOGGLE VERIFICATION. Please help me.

also the CWM says (e3) next to it.