you would have to make a few changes to tune to be able to remove the rear 02 sensor.
Alternatively you could just rescale the front 02 sensor as its capable of reading quite well down to 10 afr.
http://www.ft86club.com/forums/showthread.php?t=82875
use the values in this post
http://www.ft86club.com/forums/showp...8&postcount=16
.