So update on jetting this thing. The airbox and backfire screen were restricting airflow. This caused the carb to see higher vacuum and it was going rich past peak torque. It was droppong from 13.3:1 to the high 11s. After removing the right side of the airbox and backfire screen it's only dropping .2-.3 past peak torque, but I've had to go back up on the main jet. Currently it's a 160 main, but probably needs to go to a 165 or 167. It's interesting how big a difference small changes can make.
Everyone on thumpertalk says the backfire screen isn't a restriction, but with the side of the airbox removed it was still going rich by .6afr past peak torque. After removal it's down to only .2-.3. By the time I'm done I'll have learned a lot on jetting.