You're basically having to drown out the heat to subdue KR. When you still see KR with actual A/F having to go below 11.5, you're trying to run too much pulley. (I know this because I used to do it myself, along with many others who do or don't know it.)

If you can't run a reasonable A/F and spark when you're done with your next tuning stage that you mentioned, I'd back off the pulley & start back at a point where you see 0* with good A/F and spark 1st.

- Dave