exhaust fumes

Just check if the rods are down when the motor is idling. On the AFB and maybe T.Q. you can slid the rod cover loose and look-feel if the rod is down, just tap it with your finger, should be down, if not you found the problem.

9 inches is low. Its unlikely the rods are that rich on the lean side, if the rods are up then its on the rich side.

I would check/change the springs before messing around with the rods